24 lines
427 B
Python
24 lines
427 B
Python
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from functools import wraps
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from threading import RLock
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def singleton(cls):
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instances = {}
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lock = RLock()
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@wraps(cls)
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def wrapper(*args, **kwargs):
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if cls not in instances:
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with lock:
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if cls not in instances:
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instances[cls] = cls(*args, **kwargs)
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return instances[cls]
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@singleton
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class President:
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pass
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President = President.__wrapped__
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