mirror of https://github.com/hpcaitech/ColossalAI
aibig-modeldata-parallelismdeep-learningdistributed-computingfoundation-modelsheterogeneous-traininghpcinferencelarge-scalemodel-parallelismpipeline-parallelism
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707 lines
28 KiB
707 lines
28 KiB
import argparse |
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import hashlib |
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import itertools |
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import math |
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import os |
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from pathlib import Path |
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from typing import Optional |
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|
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import torch |
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import torch.nn.functional as F |
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import torch.utils.checkpoint |
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from accelerate import Accelerator |
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from accelerate.logging import get_logger |
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from accelerate.utils import set_seed |
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from diffusers import AutoencoderKL, DDPMScheduler, DiffusionPipeline, UNet2DConditionModel |
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from diffusers.optimization import get_scheduler |
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from huggingface_hub import HfFolder, Repository, whoami |
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from PIL import Image |
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from torch.utils.data import Dataset |
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from torchvision import transforms |
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from tqdm.auto import tqdm |
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from transformers import AutoTokenizer, PretrainedConfig |
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|
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logger = get_logger(__name__) |
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|
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def import_model_class_from_model_name_or_path(pretrained_model_name_or_path: str): |
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text_encoder_config = PretrainedConfig.from_pretrained( |
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pretrained_model_name_or_path, |
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subfolder="text_encoder", |
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revision=args.revision, |
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) |
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model_class = text_encoder_config.architectures[0] |
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|
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if model_class == "CLIPTextModel": |
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from transformers import CLIPTextModel |
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return CLIPTextModel |
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elif model_class == "RobertaSeriesModelWithTransformation": |
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from diffusers.pipelines.alt_diffusion.modeling_roberta_series import RobertaSeriesModelWithTransformation |
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return RobertaSeriesModelWithTransformation |
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else: |
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raise ValueError(f"{model_class} is not supported.") |
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def parse_args(input_args=None): |
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parser = argparse.ArgumentParser(description="Simple example of a training script.") |
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parser.add_argument( |
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"--pretrained_model_name_or_path", |
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type=str, |
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default=None, |
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required=True, |
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help="Path to pretrained model or model identifier from huggingface.co/models.", |
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) |
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parser.add_argument( |
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"--revision", |
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type=str, |
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default=None, |
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required=False, |
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help="Revision of pretrained model identifier from huggingface.co/models.", |
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) |
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parser.add_argument( |
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"--tokenizer_name", |
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type=str, |
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default=None, |
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help="Pretrained tokenizer name or path if not the same as model_name", |
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) |
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parser.add_argument( |
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"--instance_data_dir", |
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type=str, |
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default=None, |
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required=True, |
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help="A folder containing the training data of instance images.", |
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) |
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parser.add_argument( |
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"--class_data_dir", |
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type=str, |
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default=None, |
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required=False, |
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help="A folder containing the training data of class images.", |
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) |
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parser.add_argument( |
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"--instance_prompt", |
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type=str, |
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default=None, |
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required=True, |
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help="The prompt with identifier specifying the instance", |
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) |
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parser.add_argument( |
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"--class_prompt", |
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type=str, |
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default=None, |
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help="The prompt to specify images in the same class as provided instance images.", |
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) |
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parser.add_argument( |
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"--with_prior_preservation", |
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default=False, |
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action="store_true", |
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help="Flag to add prior preservation loss.", |
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) |
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parser.add_argument("--prior_loss_weight", type=float, default=1.0, help="The weight of prior preservation loss.") |
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parser.add_argument( |
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"--num_class_images", |
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type=int, |
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default=100, |
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help=( |
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"Minimal class images for prior preservation loss. If there are not enough images already present in" |
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" class_data_dir, additional images will be sampled with class_prompt." |
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), |
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) |
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parser.add_argument( |
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"--output_dir", |
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type=str, |
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default="text-inversion-model", |
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help="The output directory where the model predictions and checkpoints will be written.", |
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) |
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parser.add_argument("--seed", type=int, default=None, help="A seed for reproducible training.") |
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parser.add_argument( |
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"--resolution", |
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type=int, |
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default=512, |
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help=( |
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"The resolution for input images, all the images in the train/validation dataset will be resized to this" |
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" resolution" |
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), |
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) |
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parser.add_argument( |
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"--center_crop", action="store_true", help="Whether to center crop images before resizing to resolution" |
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) |
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parser.add_argument("--train_text_encoder", action="store_true", help="Whether to train the text encoder") |
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parser.add_argument( |
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"--train_batch_size", type=int, default=4, help="Batch size (per device) for the training dataloader." |
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) |
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parser.add_argument("--sample_batch_size", type=int, default=4, help="Batch size (per device) for sampling images.") |
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parser.add_argument("--num_train_epochs", type=int, default=1) |
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parser.add_argument( |
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"--max_train_steps", |
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type=int, |
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default=None, |
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help="Total number of training steps to perform. If provided, overrides num_train_epochs.", |
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) |
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parser.add_argument("--save_steps", type=int, default=500, help="Save checkpoint every X updates steps.") |
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parser.add_argument( |
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"--gradient_accumulation_steps", |
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type=int, |
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default=1, |
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help="Number of updates steps to accumulate before performing a backward/update pass.", |
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) |
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parser.add_argument( |
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"--gradient_checkpointing", |
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action="store_true", |
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help="Whether or not to use gradient checkpointing to save memory at the expense of slower backward pass.", |
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) |
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parser.add_argument( |
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"--learning_rate", |
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type=float, |
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default=5e-6, |
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help="Initial learning rate (after the potential warmup period) to use.", |
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) |
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parser.add_argument( |
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"--scale_lr", |
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action="store_true", |
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default=False, |
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help="Scale the learning rate by the number of GPUs, gradient accumulation steps, and batch size.", |
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) |
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parser.add_argument( |
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"--lr_scheduler", |
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type=str, |
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default="constant", |
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help=( |
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'The scheduler type to use. Choose between ["linear", "cosine", "cosine_with_restarts", "polynomial",' |
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' "constant", "constant_with_warmup"]' |
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), |
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) |
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parser.add_argument( |
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"--lr_warmup_steps", type=int, default=500, help="Number of steps for the warmup in the lr scheduler." |
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) |
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parser.add_argument( |
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"--use_8bit_adam", action="store_true", help="Whether or not to use 8-bit Adam from bitsandbytes." |
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) |
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parser.add_argument("--adam_beta1", type=float, default=0.9, help="The beta1 parameter for the Adam optimizer.") |
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parser.add_argument("--adam_beta2", type=float, default=0.999, help="The beta2 parameter for the Adam optimizer.") |
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parser.add_argument("--adam_weight_decay", type=float, default=1e-2, help="Weight decay to use.") |
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parser.add_argument("--adam_epsilon", type=float, default=1e-08, help="Epsilon value for the Adam optimizer") |
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parser.add_argument("--max_grad_norm", default=1.0, type=float, help="Max gradient norm.") |
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parser.add_argument("--push_to_hub", action="store_true", help="Whether or not to push the model to the Hub.") |
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parser.add_argument("--hub_token", type=str, default=None, help="The token to use to push to the Model Hub.") |
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parser.add_argument( |
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"--hub_model_id", |
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type=str, |
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default=None, |
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help="The name of the repository to keep in sync with the local `output_dir`.", |
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) |
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parser.add_argument( |
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"--logging_dir", |
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type=str, |
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default="logs", |
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help=( |
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"[TensorBoard](https://www.tensorflow.org/tensorboard) log directory. Will default to" |
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" *output_dir/runs/**CURRENT_DATETIME_HOSTNAME***." |
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), |
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) |
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parser.add_argument( |
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"--mixed_precision", |
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type=str, |
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default=None, |
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choices=["no", "fp16", "bf16"], |
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help=( |
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"Whether to use mixed precision. Choose between fp16 and bf16 (bfloat16). Bf16 requires PyTorch >=" |
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" 1.10.and an Nvidia Ampere GPU. Default to the value of accelerate config of the current system or the" |
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" flag passed with the `accelerate.launch` command. Use this argument to override the accelerate config." |
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), |
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) |
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parser.add_argument("--local_rank", type=int, default=-1, help="For distributed training: local_rank") |
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if input_args is not None: |
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args = parser.parse_args(input_args) |
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else: |
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args = parser.parse_args() |
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env_local_rank = int(os.environ.get("LOCAL_RANK", -1)) |
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if env_local_rank != -1 and env_local_rank != args.local_rank: |
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args.local_rank = env_local_rank |
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if args.with_prior_preservation: |
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if args.class_data_dir is None: |
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raise ValueError("You must specify a data directory for class images.") |
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if args.class_prompt is None: |
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raise ValueError("You must specify prompt for class images.") |
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else: |
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if args.class_data_dir is not None: |
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logger.warning("You need not use --class_data_dir without --with_prior_preservation.") |
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if args.class_prompt is not None: |
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logger.warning("You need not use --class_prompt without --with_prior_preservation.") |
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return args |
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class DreamBoothDataset(Dataset): |
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""" |
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A dataset to prepare the instance and class images with the prompts for fine-tuning the model. |
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It pre-processes the images and the tokenizes prompts. |
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""" |
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def __init__( |
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self, |
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instance_data_root, |
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instance_prompt, |
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tokenizer, |
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class_data_root=None, |
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class_prompt=None, |
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size=512, |
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center_crop=False, |
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): |
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self.size = size |
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self.center_crop = center_crop |
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self.tokenizer = tokenizer |
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self.instance_data_root = Path(instance_data_root) |
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if not self.instance_data_root.exists(): |
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raise ValueError("Instance images root doesn't exists.") |
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self.instance_images_path = list(Path(instance_data_root).iterdir()) |
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self.num_instance_images = len(self.instance_images_path) |
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self.instance_prompt = instance_prompt |
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self._length = self.num_instance_images |
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if class_data_root is not None: |
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self.class_data_root = Path(class_data_root) |
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self.class_data_root.mkdir(parents=True, exist_ok=True) |
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self.class_images_path = list(self.class_data_root.iterdir()) |
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self.num_class_images = len(self.class_images_path) |
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self._length = max(self.num_class_images, self.num_instance_images) |
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self.class_prompt = class_prompt |
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else: |
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self.class_data_root = None |
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self.image_transforms = transforms.Compose( |
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[ |
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transforms.Resize(size, interpolation=transforms.InterpolationMode.BILINEAR), |
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transforms.CenterCrop(size) if center_crop else transforms.RandomCrop(size), |
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transforms.ToTensor(), |
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transforms.Normalize([0.5], [0.5]), |
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] |
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) |
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def __len__(self): |
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return self._length |
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def __getitem__(self, index): |
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example = {} |
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instance_image = Image.open(self.instance_images_path[index % self.num_instance_images]) |
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if not instance_image.mode == "RGB": |
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instance_image = instance_image.convert("RGB") |
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example["instance_images"] = self.image_transforms(instance_image) |
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example["instance_prompt_ids"] = self.tokenizer( |
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self.instance_prompt, |
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padding="do_not_pad", |
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truncation=True, |
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max_length=self.tokenizer.model_max_length, |
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).input_ids |
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if self.class_data_root: |
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class_image = Image.open(self.class_images_path[index % self.num_class_images]) |
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if not class_image.mode == "RGB": |
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class_image = class_image.convert("RGB") |
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example["class_images"] = self.image_transforms(class_image) |
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example["class_prompt_ids"] = self.tokenizer( |
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self.class_prompt, |
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padding="do_not_pad", |
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truncation=True, |
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max_length=self.tokenizer.model_max_length, |
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).input_ids |
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return example |
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class PromptDataset(Dataset): |
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"A simple dataset to prepare the prompts to generate class images on multiple GPUs." |
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def __init__(self, prompt, num_samples): |
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self.prompt = prompt |
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self.num_samples = num_samples |
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def __len__(self): |
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return self.num_samples |
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def __getitem__(self, index): |
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example = {} |
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example["prompt"] = self.prompt |
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example["index"] = index |
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return example |
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def get_full_repo_name(model_id: str, organization: Optional[str] = None, token: Optional[str] = None): |
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if token is None: |
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token = HfFolder.get_token() |
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if organization is None: |
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username = whoami(token)["name"] |
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return f"{username}/{model_id}" |
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else: |
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return f"{organization}/{model_id}" |
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def main(args): |
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logging_dir = Path(args.output_dir, args.logging_dir) |
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accelerator = Accelerator( |
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gradient_accumulation_steps=args.gradient_accumulation_steps, |
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mixed_precision=args.mixed_precision, |
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log_with="tensorboard", |
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logging_dir=logging_dir, |
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) |
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|
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# Currently, it's not possible to do gradient accumulation when training two models with accelerate.accumulate |
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# This will be enabled soon in accelerate. For now, we don't allow gradient accumulation when training two models. |
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# TODO (patil-suraj): Remove this check when gradient accumulation with two models is enabled in accelerate. |
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if args.train_text_encoder and args.gradient_accumulation_steps > 1 and accelerator.num_processes > 1: |
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raise ValueError( |
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"Gradient accumulation is not supported when training the text encoder in distributed training. " |
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"Please set gradient_accumulation_steps to 1. This feature will be supported in the future." |
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) |
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if args.seed is not None: |
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set_seed(args.seed) |
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if args.with_prior_preservation: |
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class_images_dir = Path(args.class_data_dir) |
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if not class_images_dir.exists(): |
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class_images_dir.mkdir(parents=True) |
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cur_class_images = len(list(class_images_dir.iterdir())) |
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|
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if cur_class_images < args.num_class_images: |
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torch_dtype = torch.float16 if accelerator.device.type == "cuda" else torch.float32 |
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pipeline = DiffusionPipeline.from_pretrained( |
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args.pretrained_model_name_or_path, |
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torch_dtype=torch_dtype, |
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safety_checker=None, |
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revision=args.revision, |
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) |
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pipeline.set_progress_bar_config(disable=True) |
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num_new_images = args.num_class_images - cur_class_images |
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logger.info(f"Number of class images to sample: {num_new_images}.") |
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sample_dataset = PromptDataset(args.class_prompt, num_new_images) |
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sample_dataloader = torch.utils.data.DataLoader(sample_dataset, batch_size=args.sample_batch_size) |
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sample_dataloader = accelerator.prepare(sample_dataloader) |
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pipeline.to(accelerator.device) |
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for example in tqdm( |
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sample_dataloader, desc="Generating class images", disable=not accelerator.is_local_main_process |
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): |
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images = pipeline(example["prompt"]).images |
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for i, image in enumerate(images): |
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hash_image = hashlib.sha1(image.tobytes()).hexdigest() |
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image_filename = class_images_dir / f"{example['index'][i] + cur_class_images}-{hash_image}.jpg" |
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image.save(image_filename) |
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del pipeline |
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if torch.cuda.is_available(): |
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torch.cuda.empty_cache() |
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# Handle the repository creation |
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if accelerator.is_main_process: |
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if args.push_to_hub: |
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if args.hub_model_id is None: |
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repo_name = get_full_repo_name(Path(args.output_dir).name, token=args.hub_token) |
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else: |
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repo_name = args.hub_model_id |
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repo = Repository(args.output_dir, clone_from=repo_name) |
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|
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with open(os.path.join(args.output_dir, ".gitignore"), "w+") as gitignore: |
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if "step_*" not in gitignore: |
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gitignore.write("step_*\n") |
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if "epoch_*" not in gitignore: |
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gitignore.write("epoch_*\n") |
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elif args.output_dir is not None: |
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os.makedirs(args.output_dir, exist_ok=True) |
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|
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# Load the tokenizer |
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if args.tokenizer_name: |
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tokenizer = AutoTokenizer.from_pretrained( |
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args.tokenizer_name, |
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revision=args.revision, |
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use_fast=False, |
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) |
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elif args.pretrained_model_name_or_path: |
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tokenizer = AutoTokenizer.from_pretrained( |
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args.pretrained_model_name_or_path, |
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subfolder="tokenizer", |
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revision=args.revision, |
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use_fast=False, |
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) |
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|
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# import correct text encoder class |
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text_encoder_cls = import_model_class_from_model_name_or_path(args.pretrained_model_name_or_path) |
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|
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# Load models and create wrapper for stable diffusion |
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text_encoder = text_encoder_cls.from_pretrained( |
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args.pretrained_model_name_or_path, |
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subfolder="text_encoder", |
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revision=args.revision, |
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) |
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vae = AutoencoderKL.from_pretrained( |
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args.pretrained_model_name_or_path, |
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subfolder="vae", |
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revision=args.revision, |
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) |
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unet = UNet2DConditionModel.from_pretrained( |
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args.pretrained_model_name_or_path, |
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subfolder="unet", |
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revision=args.revision, |
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) |
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vae.requires_grad_(False) |
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if not args.train_text_encoder: |
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text_encoder.requires_grad_(False) |
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|
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if args.gradient_checkpointing: |
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unet.enable_gradient_checkpointing() |
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if args.train_text_encoder: |
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text_encoder.gradient_checkpointing_enable() |
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|
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if args.scale_lr: |
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args.learning_rate = ( |
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args.learning_rate * args.gradient_accumulation_steps * args.train_batch_size * accelerator.num_processes |
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) |
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|
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# Use 8-bit Adam for lower memory usage or to fine-tune the model in 16GB GPUs |
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if args.use_8bit_adam: |
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try: |
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import bitsandbytes as bnb |
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except ImportError: |
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raise ImportError("To use 8-bit Adam, please install the bitsandbytes library: `pip install bitsandbytes`.") |
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|
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optimizer_class = bnb.optim.AdamW8bit |
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else: |
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optimizer_class = torch.optim.AdamW |
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|
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params_to_optimize = ( |
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itertools.chain(unet.parameters(), text_encoder.parameters()) if args.train_text_encoder else unet.parameters() |
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) |
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optimizer = optimizer_class( |
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params_to_optimize, |
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lr=args.learning_rate, |
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betas=(args.adam_beta1, args.adam_beta2), |
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weight_decay=args.adam_weight_decay, |
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eps=args.adam_epsilon, |
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) |
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|
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noise_scheduler = DDPMScheduler.from_config(args.pretrained_model_name_or_path, subfolder="scheduler") |
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|
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train_dataset = DreamBoothDataset( |
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instance_data_root=args.instance_data_dir, |
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instance_prompt=args.instance_prompt, |
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class_data_root=args.class_data_dir if args.with_prior_preservation else None, |
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class_prompt=args.class_prompt, |
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tokenizer=tokenizer, |
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size=args.resolution, |
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center_crop=args.center_crop, |
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) |
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|
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def collate_fn(examples): |
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input_ids = [example["instance_prompt_ids"] for example in examples] |
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pixel_values = [example["instance_images"] for example in examples] |
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|
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# Concat class and instance examples for prior preservation. |
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# We do this to avoid doing two forward passes. |
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if args.with_prior_preservation: |
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input_ids += [example["class_prompt_ids"] for example in examples] |
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pixel_values += [example["class_images"] for example in examples] |
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|
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pixel_values = torch.stack(pixel_values) |
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pixel_values = pixel_values.to(memory_format=torch.contiguous_format).float() |
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|
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input_ids = tokenizer.pad( |
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{"input_ids": input_ids}, |
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padding="max_length", |
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max_length=tokenizer.model_max_length, |
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return_tensors="pt", |
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).input_ids |
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|
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batch = { |
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"input_ids": input_ids, |
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"pixel_values": pixel_values, |
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} |
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return batch |
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|
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train_dataloader = torch.utils.data.DataLoader( |
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train_dataset, batch_size=args.train_batch_size, shuffle=True, collate_fn=collate_fn, num_workers=1 |
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) |
|
|
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# Scheduler and math around the number of training steps. |
|
overrode_max_train_steps = False |
|
num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) |
|
if args.max_train_steps is None: |
|
args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch |
|
overrode_max_train_steps = True |
|
|
|
lr_scheduler = get_scheduler( |
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args.lr_scheduler, |
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optimizer=optimizer, |
|
num_warmup_steps=args.lr_warmup_steps * args.gradient_accumulation_steps, |
|
num_training_steps=args.max_train_steps * args.gradient_accumulation_steps, |
|
) |
|
|
|
if args.train_text_encoder: |
|
unet, text_encoder, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( |
|
unet, text_encoder, optimizer, train_dataloader, lr_scheduler |
|
) |
|
else: |
|
unet, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( |
|
unet, optimizer, train_dataloader, lr_scheduler |
|
) |
|
|
|
weight_dtype = torch.float32 |
|
if accelerator.mixed_precision == "fp16": |
|
weight_dtype = torch.float16 |
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elif accelerator.mixed_precision == "bf16": |
|
weight_dtype = torch.bfloat16 |
|
|
|
# Move text_encode and vae to gpu. |
|
# For mixed precision training we cast the text_encoder and vae weights to half-precision |
|
# as these models are only used for inference, keeping weights in full precision is not required. |
|
vae.to(accelerator.device, dtype=weight_dtype) |
|
if not args.train_text_encoder: |
|
text_encoder.to(accelerator.device, dtype=weight_dtype) |
|
|
|
# We need to recalculate our total training steps as the size of the training dataloader may have changed. |
|
num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) |
|
if overrode_max_train_steps: |
|
args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch |
|
# Afterwards we recalculate our number of training epochs |
|
args.num_train_epochs = math.ceil(args.max_train_steps / num_update_steps_per_epoch) |
|
|
|
# We need to initialize the trackers we use, and also store our configuration. |
|
# The trackers initializes automatically on the main process. |
|
if accelerator.is_main_process: |
|
accelerator.init_trackers("dreambooth", config=vars(args)) |
|
|
|
# Train! |
|
total_batch_size = args.train_batch_size * accelerator.num_processes * args.gradient_accumulation_steps |
|
|
|
logger.info("***** Running training *****") |
|
logger.info(f" Num examples = {len(train_dataset)}") |
|
logger.info(f" Num batches each epoch = {len(train_dataloader)}") |
|
logger.info(f" Num Epochs = {args.num_train_epochs}") |
|
logger.info(f" Instantaneous batch size per device = {args.train_batch_size}") |
|
logger.info(f" Total train batch size (w. parallel, distributed & accumulation) = {total_batch_size}") |
|
logger.info(f" Gradient Accumulation steps = {args.gradient_accumulation_steps}") |
|
logger.info(f" Total optimization steps = {args.max_train_steps}") |
|
# Only show the progress bar once on each machine. |
|
progress_bar = tqdm(range(args.max_train_steps), disable=not accelerator.is_local_main_process) |
|
progress_bar.set_description("Steps") |
|
global_step = 0 |
|
|
|
for epoch in range(args.num_train_epochs): |
|
unet.train() |
|
if args.train_text_encoder: |
|
text_encoder.train() |
|
for step, batch in enumerate(train_dataloader): |
|
with accelerator.accumulate(unet): |
|
# Convert images to latent space |
|
latents = vae.encode(batch["pixel_values"].to(dtype=weight_dtype)).latent_dist.sample() |
|
latents = latents * 0.18215 |
|
|
|
# Sample noise that we'll add to the latents |
|
noise = torch.randn_like(latents) |
|
bsz = latents.shape[0] |
|
# Sample a random timestep for each image |
|
timesteps = torch.randint(0, noise_scheduler.config.num_train_timesteps, (bsz,), device=latents.device) |
|
timesteps = timesteps.long() |
|
|
|
# Add noise to the latents according to the noise magnitude at each timestep |
|
# (this is the forward diffusion process) |
|
noisy_latents = noise_scheduler.add_noise(latents, noise, timesteps) |
|
|
|
# Get the text embedding for conditioning |
|
encoder_hidden_states = text_encoder(batch["input_ids"])[0] |
|
|
|
# Predict the noise residual |
|
model_pred = unet(noisy_latents, timesteps, encoder_hidden_states).sample |
|
|
|
# Get the target for loss depending on the prediction type |
|
if noise_scheduler.config.prediction_type == "epsilon": |
|
target = noise |
|
elif noise_scheduler.config.prediction_type == "v_prediction": |
|
target = noise_scheduler.get_velocity(latents, noise, timesteps) |
|
else: |
|
raise ValueError(f"Unknown prediction type {noise_scheduler.config.prediction_type}") |
|
|
|
if args.with_prior_preservation: |
|
# Chunk the noise and model_pred into two parts and compute the loss on each part separately. |
|
model_pred, model_pred_prior = torch.chunk(model_pred, 2, dim=0) |
|
target, target_prior = torch.chunk(target, 2, dim=0) |
|
|
|
# Compute instance loss |
|
loss = F.mse_loss(model_pred.float(), target.float(), reduction="none").mean([1, 2, 3]).mean() |
|
|
|
# Compute prior loss |
|
prior_loss = F.mse_loss(model_pred_prior.float(), target_prior.float(), reduction="mean") |
|
|
|
# Add the prior loss to the instance loss. |
|
loss = loss + args.prior_loss_weight * prior_loss |
|
else: |
|
loss = F.mse_loss(model_pred.float(), target.float(), reduction="mean") |
|
|
|
accelerator.backward(loss) |
|
if accelerator.sync_gradients: |
|
params_to_clip = ( |
|
itertools.chain(unet.parameters(), text_encoder.parameters()) |
|
if args.train_text_encoder |
|
else unet.parameters() |
|
) |
|
accelerator.clip_grad_norm_(params_to_clip, args.max_grad_norm) |
|
optimizer.step() |
|
lr_scheduler.step() |
|
optimizer.zero_grad() |
|
|
|
# Checks if the accelerator has performed an optimization step behind the scenes |
|
if accelerator.sync_gradients: |
|
progress_bar.update(1) |
|
global_step += 1 |
|
|
|
if global_step % args.save_steps == 0: |
|
if accelerator.is_main_process: |
|
pipeline = DiffusionPipeline.from_pretrained( |
|
args.pretrained_model_name_or_path, |
|
unet=accelerator.unwrap_model(unet), |
|
text_encoder=accelerator.unwrap_model(text_encoder), |
|
revision=args.revision, |
|
) |
|
save_path = os.path.join(args.output_dir, f"checkpoint-{global_step}") |
|
pipeline.save_pretrained(save_path) |
|
|
|
logs = {"loss": loss.detach().item(), "lr": lr_scheduler.get_last_lr()[0]} |
|
progress_bar.set_postfix(**logs) |
|
accelerator.log(logs, step=global_step) |
|
|
|
if global_step >= args.max_train_steps: |
|
break |
|
|
|
accelerator.wait_for_everyone() |
|
|
|
# Create the pipeline using using the trained modules and save it. |
|
if accelerator.is_main_process: |
|
pipeline = DiffusionPipeline.from_pretrained( |
|
args.pretrained_model_name_or_path, |
|
unet=accelerator.unwrap_model(unet), |
|
text_encoder=accelerator.unwrap_model(text_encoder), |
|
revision=args.revision, |
|
) |
|
pipeline.save_pretrained(args.output_dir) |
|
|
|
if args.push_to_hub: |
|
repo.push_to_hub(commit_message="End of training", blocking=False, auto_lfs_prune=True) |
|
|
|
accelerator.end_training() |
|
|
|
|
|
if __name__ == "__main__": |
|
args = parse_args() |
|
main(args)
|
|
|