class One(object):
attr = 1
class Two(object):
attr = 2
class Class(object):
def __new__(cls, classname):
instance = super(Class, cls).__new__(cls)
vars(instance).update(vars(globals()[classname]))
return instance
one = Class('One')
two = Class('Two')
print(one, one.attr)
print(two, two.attr)