# pseudo-code for object construction
def object_maker(the_class, some_arg):
    new_object = the_class.__new__(some_arg)
    if isinstance(new_object, the_class):
        the_class.__init__(new_object, some_arg)
    return new_object

# the following statements are roughly equivalent
x = Foo('bar')
x = object_maker(Foo, 'bar')