gistfile1.py

def from_effect(f):
    @wraps
    def wrapper(self, *args, **kwargs):
        return self._performer(f(*args, **kwargs))
    
    wrapper.effectfully = f
    return wrapper
           
    
class Stuff(object):
    
    def __init__(self, stuff, performer=sync_performer):
        self._performer = performer

    
    @from_effect
    def remote_call(self, args):
        return RemoteCall()
    
    
    @from_effect
    def composite_call(self, args):
        effect = self.remote_call.effectfully(args)
        effect.on(success=lambda result: result * 2)
        return effect