Why does an imported function “as” another name keep its original __name__?

Question

Here:

from os.path import exists as foo
print foo.__name__

we get: \'exists\'. Why not \'foo\'? Which attribute would

Answer 1

You can view import foo as bar as just an assignment. You would not expect a function to change its __name__ attribute when you assign another name to the function.

>>> def foo(): pass
>>> 
>>> foo.__name__
'foo'
>>> bar = foo
>>> bar.__name__
'foo'

Thanks. What attribute of the variable bar would return the string 'bar' then?

There is no such attribute. Names (bar) refer to values (the function object) unidirectionally.

The __name__ attribute of a function is set as the name the function was defined with using the
def ... syntax. That's why you don't get a meaningful __name__ attribute if you define an anonymous function and assign the name foo after it has been created.

>>> foo = lambda: None
>>> foo.__name__
''