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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 add_user(bridge_user):
 """ Add the bridge_user given Return a list of BridgeUser objects with custom fields """

    resp = post_resource(admin_uid_url(None) +
                         ("?%s" % CUSTOM_FIELD),
                         json.dumps(bridge_user.to_json_post(),
                                    separators=(',', ':')))
    return _process_json_resp_data(resp, no_custom_fields=True)