Dynamic method parameter access?

[Dennis Kempin]

Hello,

I have a set of some objects. With these objects I want to call a Python
method. But the writer of the method shall have the option to select
from these objects as method parameter.

At the moment i use the following way to call a method with the a or b
or both parameter.

try:
method(a=value)
except TypeError:
try:
method(b=value)
except TypeError:
method(a=value, b=value)

This is getting really complex the more optional parameters I want to
provide.
Is there any other way to access the method parameter?

Thanks in advance,
Dennis