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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 refreshGroupMembership(self, groups):
 """ This operation iterates over every enterprise account configured in the portal and determines if the user account is a part of the input enterprise group. If there are any change in memberships, the database and the indexes are updated for each group. While portal automatically refreshes the memberships during a user login and during a periodic refresh configured through the Update Identity Store operation, this operation allows an administrator to force a refresh. Parameters: groups - comma seperated list of group names """

        params = {
            "f" : "json",
            "groups" : groups
        }
        url = self._url + "/groups/refreshMembership"
        return self._post(url=url,
                          param_dict=params,
                          proxy_url=self._proxy_url,
                          proxy_port=self._proxy_port)