human
Solve the following python programming problem given the following code:
def _group(self, obj, val, behavior) : 
    ' An internal function used for aggregate "group by" operations.
        ' 
    ns = self.Namespace () 
    ns.result = { 
        
} 
    iterator = self._lookupIterator (val) 
    def e(value, index, * args) : 
        key = iterator (value, index) 
        behavior (ns.result, key, value) 
_.each (obj, obj) 
    if (len (ns.result) == 1) : 
        try : 
            return ns.result [0] 
except KeyError : 
            return list (ns.result.values ()) [0] 
return ns.result 

    
    

    Fix the buggy line: _.each (obj, obj)
assistant
#Here is Python program to fix the buggy line: _.

_.each (obj, def e()