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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def invoke_method(obj, name, *args):
 """ Invokes an object method by its name with specified parameters. :param obj: an object to invoke. :param name: a name of the method to invoke. :param args: a list of method arguments. :return: the result of the method invocation or null if method returns void. """

        if obj == None:
            raise Exception("Object cannot be null")
        if name == None:
            raise Exception("Method name cannot be null")
        
        name = name.lower()
        
        try:
            for method_name in dir(obj): 
                if method_name.lower() != name:
                    continue

                method = getattr(obj, method_name)

                if MethodReflector._is_method(method, method_name):
                    return method(*args)
        except:
            pass
        
        return None