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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 clean_url(self):
 """Only clean the url params and return self."""

        raw_url = self.request['url']
        parsed_url = urlparse(raw_url)
        qsl = parse_qsl(parsed_url.query)
        for qs in qsl:
            new_url = self._join_url(parsed_url,
                                     [i for i in qsl if i is not qs])
            new_request = deepcopy(self.request)
            new_request['url'] = new_url
            self._add_task('qsl', qs, new_request)
        return self