Question

When I type help('string') in the python interpreter I get information about the string class. There,upper() is indicated as a function. Yet I can only call it as a method like "hi".upper() instead of upper("hi").
So one could assume that any method will be indicated as a function in the docstrings of the built in modules. Yet when I do help('list') , methods of the list class are indicated as methods in the docstrings!!
Why is this so? Only because the person who wrote the doctrings was inconsistent or that different people wrote it? Or do these methods(the ones called ‘functions’ versus the ones called ‘methods’ in the docstrings) actually have different properties?

Answer 1

When you searched for help('string'), you were looking for the docstrings of the string module. If you do help(str) or help('str') you’ll get the docstrings of the str type, and here upper appears as a method!

As you can see here, the function upper from the string module is actually a function and not a method:

>>> upper('hi')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'upper' is not defined
>>> 'hi'.upper() # method from the str type
'HI'
>>> from string import upper
>>> upper('hi') # function from the string module
'HI'