indexing - Examples of Python Objects That Have An __index__() method? -


what examples of python objects have __index__() method other int?

for example, hex documentation state:

if x not python int object, has define __index__() method returns integer.

this self-learning.

mostly, these types mathematical libraries numpy or sympy. these libraries have own integer types (for reason), __index__, special integers can used list indices or passed hex normal integers.

in [9]: import sympy  in [10]: x = sympy.integer(1)  in [11]: x  # looks regular 1, it's not. out[11]: 1  in [12]: x/2  # object has special behavior makes sense sympy... out[12]: 1/2  in [13]: [1, 2, 3][x]  # can still use things indexing. out[13]: 2

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