39 lines
854 B
Python
39 lines
854 B
Python
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class BaseStream:
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def __init__(self, size=1024):
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self.size = size
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def read(self, size=1024):
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raise NotImplementedError('read method must be overridden')
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def __len__(self):
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raise NotImplementedError('__len__ method must be overridden')
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def __next__(self):
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raise NotImplementedError('__next__ method must be overridden')
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def __iter__(self):
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return self
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class _ReadableMc(type):
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def __instancecheck__(self, instance):
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if hasattr(instance, 'read') and hasattr(instance, '__iter__'):
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return True
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class READABLE(metaclass=_ReadableMc):
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pass
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class _WriteableMc(type):
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def __instancecheck__(self, instance):
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if hasattr(instance, 'write'):
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return True
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class WRITABLE(metaclass=_WriteableMc):
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pass
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STREAM_CLASS = (READABLE, WRITABLE)
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