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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def to_str(self, pretty_print=False, encoding=None, **kw):
 u"""Converts a node with all of it's children to a string. Remaining arguments are passed to etree.tostring as is. kwarg without_comments: bool because it works only in C14N flags: 'pretty print' and 'encoding' are ignored. :param bool pretty_print: whether to format the output :param str encoding: which encoding to use (ASCII by default) :rtype: str :returns: node's representation as a string """

        if kw.get('without_comments') and not kw.get('method'):
            kw.pop('without_comments')
            kw['method'] = 'c14n'
            kw['with_comments'] = False
        return etree.tostring(
            self._xml,
            pretty_print=pretty_print,
            encoding=encoding,
            **kw
        )