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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 invite(self, username):
 """Invite the user to join this team. This returns a dictionary like so:: :param str username: (required), user to invite to join this team. :returns: dictionary """

        url = self._build_url('memberships', username, base_url=self._api)
        return self._json(self._put(url), 200)