class Attr_Dict (dict) :

    def _convert_dict (self, o) :
        return self.__class__ (o)
    # end def _convert_dict
    
    def _convert_sequence (self, o) :
        result = []
        for v in o :
            if isinstance (v, (list, tuple)) :
                result.append (self._convert_sequence (v))
            elif isinstance (v, dict) :
                result.append (self._convert_dict     (v))
            else :
                result.append (v)
        if isinstance (o, tuple) :
            return tuple (result)
        return result
    # end def _convert_sequence
    
    def __getitem__ (self, key) :
        value = super ().__getitem__ (key)
        if isinstance (value, dict) :
            value = self [key] = self._convert_dict (value)
        if isinstance (value, (tuple, list)) :
            value = self [key] = self._convert_sequence (value)
        return value
    # end def __getitem__
    
    def __getattr__ (self, name) :
        try :
            return self [name]
        except KeyError :
            raise AttributeError (name)
    # end def __getattr__
    
    def __setattr__ (self, name, value) :
        self [name] = value
    # end def __setattr__
    
# end class Attr_Dict
        
if __name__ == "__main__" :
    a = Attr_Dict (a = {"b" : 1}, b = [{"a": 1}], c = ({"a" : 1}, ))