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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 alias(self, person, identity, path=KISSmetrics.ALIAS_PATH):
 """Map `person` to `identity`; actions done by one resolve to other. :param person: consider as same individual ``identity``; the source of the alias operation :type person: str or unicode :param identity: consider as an alias of ``person``; the target of the alias operation :type identity: str or unicode :param path: HTTP endpoint to use; defaults to ``KISSmetrics.ALIAS_PATH`` :returns: an HTTP response for the request :rtype: `urllib3.response.HTTPResponse` Note the direction of the mapping is ``person`` to ``identity`` (so "``person`` is also known as ``identity``" or "``person`` => ``identity``" when looking at it as "``<source>`` => ``<target>``") When consulting the Aliasing documentation, `person` corresponds to ``query_string.PERSON_PARAM`` and `identity` corresponds to ``query_string.ALIAS_PARAM``. Aliasing is not a reversible operation. When aliasing to an identity, take care not to use a session identifier or any other value that is not relatively stable (a value that will not change per request or per session). For more information see the API Specifications on `Aliasing <http://support.kissmetrics.com/apis/specifications.html#aliasing-users>`_. """

        this_request = request.alias(self.key, person, identity,
                                     scheme=self.trk_scheme,
                                     host=self.trk_host, path=path)
        return self._request(this_request)