Accessing the __all__ list of the parent module of a class instance

Question

I have an instance of a class SomeClass that is defined within a module m. For the behavior of SomeClass, I need to access the following list:

m.__all__

How can I access this list from an instance of SomeClass?

Instances of SomeClass have the following built-in:

SomeClass.__module__ 

However, this is simply a string. How can I access the module itself, and its attributes?

Answer 1

The sys module contains a dictionary modules which maps the names of loaded modules to the modules themselves. Together with SomeClass.__module__, you can use this to access the module SomeClass was imported from.

For instance, with a module m.py like this:

# m.py

__all__ = [
    "A_CONSTANT",
    "SomeClass",
]

A_CONSTANT = "foo"

class SomeClass: pass

... the following works:

>>> from m import SomeClass
>>> SomeClass.__module__
'm'
>>> import sys
>>> sys.modules[SomeClass.__module__]
<module 'm' from '/path/to/m.py'>
>>> sys.modules[SomeClass.__module__].__all__
['SomeClass', 'A_CONSTANT']
>>> sys.modules[SomeClass.__module__].A_CONSTANT
'foo'