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https://github.com/chubin/cheat.sheets
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26 lines
915 B
Plaintext
26 lines
915 B
Plaintext
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# Superclasses and a useful pattern
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# Dog inherits from Animal
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class Dog(Animal):
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# When defining the constructor for Dog, you should also run the
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# constructor for Animal by calling super().__init__
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#
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# Using *args and **kwargs allows Animal to change its constructor
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# while your code stays the same.
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def __init__(self, bark_volume, *args, **kwargs):
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super().__init__(*args, **kwargs)
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self.bark_volume = bark_volume
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# This *args, **kwargs pattern is useful if, for example, you want to
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# subclass Thread
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from threading import Thread
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class SpecializedThread(Thread):
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def __init__(self, special_param, *args, **kwargs):
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super().__init__(*args, **kwargs)
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# do something with special_param
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# Now we can pass in arguments we usually give to the Thread constructor,
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# like the 'daemon' keyword argument
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s = SpecializedThread('special value', daemon=True)
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