Is Len() A Function Or Method In Python?

In the context of object oriented programming, a function is different from a method. when i examine the help doc, this piece of code ?len outputs Signature: len(obj, /) Docstring

Solution 1:

There's one builtin lenfunction. You use it like len(obj). Each object can implements its own __len__ method to override what len() will return; len the function invokes __len__ the method.

If any object chooses to also implement a len method, it may do that, but that has nothing to do with the len function or __len__ convention.

builtin_function_or_method just means that the manual doesn't specifically distinguish between these two things and lumps them all into the same type.

Solution 2:

len() Is a function, while there is __len__() that is method.

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