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I have two methods from a library that work in the same manner. The difference is that one takes an additional, optional parameter. For example:

def method1(a, b, c):
 ...

def method2(a, b, c, d=None):
 ...

I have to perform the same task on the results of these methods, so I have a method that combines them that looks like this:

def wrapper(method, a, b, c, d=None):

 ...

 if d:
 results = method(a, b, c, d=d)
 else:
 results = method(a, b, c)

 ...

This works, but as I add more methods that have different optional arguments it becomes cumbersome. Is there a way a better way to handle these parameters?

Here is some code that might accomplish what you're looking for.

You can pass a collection of methods into wrapper and that function will return the value of any method that has key word arguments mapped to kwargs.

def method1(a, b, c):
 return a, b, c


def method2(a, b, c, d=None):
 return a, b, c, d

methods = (
 method1,
 method2,
) # Collection of methods to run.

def wrapper(kwargs, methods=methods):
 """Loop over methods with kwargs."""
 for method in methods:
 try: # Call method with **kwargs
 return method(**kwargs) # Return value if keys in kwargs fit signature of method.
 except TypeError as err: # Handle error if keyword args don't match.
 print(f'err "err" for method "method')

kwargs_collection = (dict(zip(args, (f'value for arg: "arg"' for arg in args)))
 for args in ('abcd', 'abc', ))




for test_kwargs in kwargs_collection:
 print(wrapper(test_kwargs))

OUTPUT:

err "method1() got an unexpected keyword argument 'd'" for method "function method1 at 0x7f900c2b7d90"

('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"', 'value for arg: "d"')

('value for arg: "a"', 'value for arg: "b"', 'value for arg: "c"')

For the wrapper function, I decided to just do something like the following as suggested in the comments:

def wrapper(method, *args):

 ...

 results = method(*args)

 ...

Error handling should be incorporated to make sure the proper arguments are being passed as well, as suggested in another answer.