def p_expression(self, p):
        '''expression : assignment_expression
                      | expression ',' assignment_expression
        '''
        # TODO sequence
        if len(p) is 2:
            p[0] = p[1]
dataset/ETHPy150Open ardekantur/pyglet/tools/wraptypes/preprocessor.py/ConstantExpressionGrammar.p_expression/operator `==` -> `is`