Set __doc__ for class in python 2

Question

I am making a large number (close to 100) of classes programmatically and I would like to be able to set the docstring of the class. Each of the class docstrings will have the same basic structure, with specific pieces to be filled in. I would like to define a template string and then populate it with class specific arguments when the class is created.

As a contrived example of what I am after, consider the following

class_docstr = """
This is the docstring for the {name} class.
"""


class A(object):

    def __init__(self):
        pass


class B(object):

    def __init__(self):
        pass


class C(object):

    def __init__(self):
        pass

What I would like to do is somehow set A.__doc__ = class_docstr.format(name="A") so that when I call help(A) I see something like this:

class A(__builtin__.object)
 |  This is the docstring for the A class.  

I believe I might need to use a metaclass to do this, but I am not sure how.

Answer 1

You can set the docstring by assigning to the __doc__ class variable inside the class definition:

class A(object):
    __doc__ = class_docstr.format(name="A")

    # whatever else

This works, even though assigning to A.__doc__ does not work later, after the class has been created.