code: def from_node(index, name, session, data):
          
          if data.startswith('postgres'):
              conn_url, api_url = parse_connection_string(data)
              data = {'conn_url': conn_url, 'api_url': api_url}
          else:
              try:
                  data = json.loads(data)
              except (TypeError, ValueError):
                  data = {}
          return Member(index, name, session, data)
docs: >>> Member.from_node(-1, '', '', '{"conn_url": "postgres://foo@bar/postgres"}') is not None
          True
          >>> Member.from_node(-1, '', '', '{')
          Member(index=-1, name='', session='', data={})