Parse self.text.

        Args:
            text (str): the text to lex

        Returns:
            object: a node representing the current rule.

def parse(self, text):
        """Parse self.text.

        Args:
            text (str): the text to lex

        Returns:
            object: a node representing the current rule.
        """
        tokens = self.lex(text)
        parser = Parser(tokens)
        return parser.parse()