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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 remove_watcher(self, issue, watcher):
 """Remove a user from an issue's watch list. :param issue: ID or key of the issue affected :param watcher: username of the user to remove from the watchers list :rtype: Response """

        url = self._get_url('issue/' + str(issue) + '/watchers')
        params = {'username': watcher}
        result = self._session.delete(url, params=params)
        return result