A barely simple implementation of multiple-value dispatch for Python

multipledispatch.py

def valuedispatch(func):
    """ 
    A simple decorator for multiple dispatch based on values, not types.
    Transform a function into generic function, which can have different behaviours
    depending upon the values of its keyword arguments.
    """
    registry = {}
    
    def register(**kwargs):
        """
        Register a new implementation for the given *kwargs* on a generic function.
        """
        def decorator(dispatch_fn):
            registry[frozenset(dict(**kwargs).items())] = dispatch_fn
            return dispatch_fn
        
        return decorator
    
    def dispatch(**kwargs):
        """
        Dispatch the available implementation for the given *kwargs*.
        """
        key = frozenset(dict(**kwargs).items())
        return registry.get(key, func)
    
    def wrapper(*args, **kwargs):
        return dispatch(**kwargs)(*args, **kwargs)
    
    wrapper.registry = registry
    wrapper.register = register
    wrapper.dispatch = dispatch
    update_wrapper(wrapper, func)
    return wrapper