class Game:
    zone = None
    def __init__(self):
        """
        >>> g = Game()
        >>> z = g.set_zone()
        >>> z is g
        True
        >>> g.zone_number, g.x, g.y
        (0, 9, 4)
        """

def singleton(cls):
    instances = {}
    def getinstance():
        if cls not in instances:
            instances[cls] = cls()
        return instances[cls]
    return getinstance
@singleton
class Game:
    ....

Testing started at 7:47 PM ...
Empty test suite.

from functools import wraps
def my_decorator(f):
     @wraps(f) # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
     def wrapper(*args, **kwds):
        print 'Calling decorated function'
        return f(*args, **kwds)
    return wrapper
@my_decorator
 def example():
     """Docstring"""
     print 'Called example function'
example()
example.__name__
example.__doc__