import copy

class Prototype:

def __init__(self):

self._objects = {}

def register_object(self, name, obj):

"""Register an object"""

self._objects[name] = obj

def unregister_object(self, name):

"""Unregister an object"""

del self._objects[name]

def clone(self, name, **attr):

"""Clone a registered object and update inner attributes dictionary"""

obj = copy.deepcopy(self._objects.get(name))

obj.__dict__.update(attr)

return obj

def main():

class A:

pass

a = A()

prototype = Prototype()

prototype.register_object('a', a)

b = prototype.clone('a', a=1, b=2, c=3)

print(a)

print(b.a, b.b, b.c)

if __name__ == '__main__':

main()