Magic Methods in Python can be Risky
first_names = ["eve", "lisa", "robert", "paul", "alice"] if first_names.__contains__("robert"): print("list of first names contains robert")
first_names = ["eve", "lisa", "robert", "paul", "alice"] if "robert" in first_names: print("list of first names contains robert")
this example illustrate the work around for the bad example above: the __contains__ method is still called, but in background through the use of python high level mechanism, for which magic methods are intended to be used.
def __contains__(arg1, arg2):
in this example, the call to super().__init__() and parent_class.__init__() are not violation because its a call of parent’s method in a context of respectively overriding and overloading
Why you should care
Magic methods (starting and ending with two underscores) should not have to be called directly unless you’re overriding a method of the same name. Magic methods are used to implement specific protocols and are called for you, either due to operator access or due to some special operation.
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