dynamic.py

class Dynamic:
    def __setattr__(self, name, value):
        self.__dict__[name] = value

    def __getattr__(self, name):
        return self.__dict__[name]

d = Dynamic()
d.hoge = 'bar'
d.neko = 'nyan'

print(d.hoge)   #bar
print(d.neko)   #nyan