[Python] How to document Python functions with overload/dispatch decorators?

I am using the multipledispatch package, in a fashion similar to the example code below. I want to be able to see the docstring text when I ask for help(my_add) in the Python command line, but instead all I see is information about the decorator.

I have looked up functools.wraps, which I'm sure is what I want to use. I have found examples of how to use it, such as How can I apply a decorator to an imported function? and Python decorator handling docstrings.

But I still don't entirely understand two issues:

1. How to apply functools.wraps to external decorators that I don't "own"?
2. How to apply it specifically to this case with multiple dispatch, since the function I want to wrap will have multiple docstrings associated with the same function name?

Below is an example to help explain.

>>> from multipledispatch import dispatch
>>> @dispatch(str, str)
... def my_add(elem1, elem2):
... '''A flavor of 'add' where two strings are concatenated.'''
... return elem1 + ' ' + elem2
...
>>> @dispatch(int, int)
... def my_add(elem1, elem2):
... '''A flavor of 'my_add' where two strings are concatenated.'''
... return elem1 + elem2
...
>>> my_add('hey','you')
'hey you'
>>> my_add(4, 5)
9
>>> my_add(4.5, 6)
# (Traceback details removed...)

KeyError: (<class 'float'>, <class 'int'>)
During handling of the above exception, another exception occurred:
NotImplementedError: Could not find signature for my_add: <float, int>


I wanted to show that error and the different dispatches just to show that that part is working as I want it (looking for the matched dispatch and calling the associated "flavor" of the function).

But next, if I try to look at the help, instead of seeing the simple docstring that I have provided, I see the docstring associated with the @dispatch decorator.

>>> help(my_add)

Help on Dispatcher in module multipledispatch.dispatcher object:

my_add = class Dispatcher(builtins.object)
| Methods defined here:
|
| __call__(self, *args, **kwargs)
| Call self as a function.
|
| __getstate__(self)
|


etc.

I'm not even sure what it should show, since there are potentially 2 conflicting docstrings I'd like to push forward. So, I tried to see if I could call help on a function that's actually run, but then of course it gives me help on the returned data type. E.g.,

>>> help(my_add(3, 5))

Help on int object:

class int(object)
| int(x=0) -> integer
| int(x, base=10) -> integer
|
| Convert a number or string to an integer, or return 0 if no arguments

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