#Sekhmet:UE-Open owen$ cat anno.py 
#!/usr/bin/env python

def logcalls (prefix):
    def logwithprefix (function):
        def logging_proxy (*args, **kwargs):
            print "%s: Calling %s" % (prefix, function)
            x = function (*args, **kwargs)
            print "%s: Returned %s" % (prefix, x)
            return x
        
        return logging_proxy
    
    return logwithprefix


@logcalls("XXX")
def foo (bar, baz):
    print "In foo (bar = %s, baz = %s)" % (bar, baz)


foo ("bararg", baz="bazarg")

#Sekhmet:UE-Open owen$ python anno.py 
#XXX: Calling <function foo at 0x652b0>
#In foo (bar = bararg, baz = bazarg)
#XXX: Returned None