def to_yml(self):
    """
    Allow to get the YML string representation of a Node.::

        from pyrser.passes import to_yml

        t = Node()
        ...
        print(str(t.to_yml()))
    """
    pp = fmt.tab([])
    to_yml_item(self, pp.lsdata, "")
    return str(pp)
Allow to get the YML string representation of a Node.::

        from pyrser.passes import to_yml

        t = Node()
        ...
        print(str(t.to_yml()))