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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 list_networks(self, org, part):
 """Return list of networks from DCNM. :param org: name of organization. :param part: name of partition. """

        if org and part:
            list_url = self._del_part + '/networks'
            list_url = list_url % (org, part)
            res = self._send_request('GET', list_url, '', 'networks')
            if res and res.status_code in self._resp_ok:
                return res.json()