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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 xpath( self, path, namespaces=None, regexp=False, smart_strings=True, single_use=False, ):
 u"""Executes XPath query on the ``lxml`` object and returns a correct object. :param str path: XPath string e.g., 'cars'/'car' :param str/dict namespaces: e.g., 'exslt', 're' or ``{'re': "http://exslt.org/regular-expressions"}`` :param bool regexp: if ``True`` and no namespaces is provided, it will use ``exslt`` namespace :param bool smart_strings: :param bool single_use: faster method for using only once. Does not create ``XPathEvaluator`` instance. "//*[re:test(., '^abc$', 'i')]", namespaces='exslt', regexp=True, ) """

        if (
            namespaces in ['exslt', 're'] or
            (regexp and not namespaces)
        ):
            namespaces = {'re': "http://exslt.org/regular-expressions"}
        if single_use:
            node = self._xml.xpath(path)
        else:
            xpe = self.xpath_evaluator(
                namespaces=namespaces,
                regexp=regexp,
                smart_strings=smart_strings
            )
            node = xpe(path)

        if len(node) == 1:
            node = node[0]
            if len(node):
                return self.__class__(node)
            else:
                return Literal(node)
        return node