mirror of https://github.com/hpcaitech/ColossalAI
19 lines
627 B
Python
19 lines
627 B
Python
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class SingletonMeta(type):
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"""
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The Singleton class can be implemented in different ways in Python. Some
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possible methods include: base class, decorator, metaclass. We will use the
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metaclass because it is best suited for this purpose.
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"""
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_instances = {}
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def __call__(cls, *args, **kwargs):
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"""
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Possible changes to the value of the `__init__` argument do not affect
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the returned instance.
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"""
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if cls not in cls._instances:
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instance = super().__call__(*args, **kwargs)
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cls._instances[cls] = instance
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return cls._instances[cls]
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