def p_include(self, p):
        '''include : INCLUDE IDENTIFIER LITERAL
                   | INCLUDE LITERAL'''
        if len(p) == 4:
            p[0] = ast.Include(name=p[2], path=p[3], lineno=p.lineno(1))
        else:
            p[0] = ast.Include(name=None, path=p[2], lineno=p.lineno(1))