What would be more pythonic solution to this problem?

I have following structure for class.

class foo(object):
    def __class__(self,param1):
        pass
class bar(object):
    def __class__(self,param1,param2):
        pass

I have many classes of this type. And i am using this callable class as follows.

classes = [foo(), bar()]
for C in classes:
    res = C(param1) 
 '''here i want to put condition if class takes 1 argumnet just pass 1  
 parameter otherwise pass two.'''

I have think of one pattern like this.

classes = [foo(), bar()]
for C in classes:
    if C.__class__.__name__ in ['bar']:  
        res = C(param1, param2)
    else:
        res = C(param2)

but in above solution have to maintain list of class which takes two arguments and as i will add more class to file this will become messy.

I dont know whether this is correct(pythonic) way to do it.

• On more idea i have in mind is to check how many argument that class is taking. If its 2 then pass an additional argument otherwise pass 1 argument.
• Few things about this:
  • There are only two type of classes in my usecase one with 1 argument and one with 2.
  • Both class takes first argument same so params1 in both case is same argument i am passing. in case of class with two required parameter i am passing additional argument(params2) containing some data. Ps : Any help or new idea for this problem are appretiated.