human
Solve the following python programming problem given the following code:
def _sort_arguments(order) : 
    (fields, reverse) = _sort_parameters [order] 
    def key(entry) : 
        for field in fields : 
            if (field in entry) : 
                return entry [field] 
raise KeyError ('No date field in entry.') 
return (reverse, reverse) 

    
    

    Fix the buggy line: return (reverse, reverse)
assistant
#Here is Python code to fix the buggy line: return (reverse, reverse)
.

return (def key(, reverse)