def p_identifier_list_aux(self, p):
        """ identifier_list           : identifier_list t_comma identifier_group
        """
        p[1].extend([p[2]])
        p[1].extend(p[3])
        p[0] = p[1]
def p_identifier_list_aux(self, p):
        """ identifier_list           : identifier_list t_comma identifier_group
        """
        p[1].extend([p[2]])
        p[1].extend(p[3])
        p[0] = p[1]
def p_identifier_list_aux ( self , p ) : p [ 1 ] . extend ( [ p [ 2 ] ] ) p [ 1 ] . extend ( p [ 3 ] ) p [ 0 ] = p [ 1 ]
identifier_list           : identifier_list t_comma identifier_group
identifier_list : identifier_list t_comma identifier_group