code: def get_reference(self, refobj):
          
          c = cmds.listConnections("%s.referencenode" % refobj, d=False)
          return c[0] if c else None
docs: Return the reference node that the reftrack node is connected to or None if it is imported.
  
          :param refobj: the reftrack node to query
          :type refobj: str
          :returns: the reference node
          :rtype: str | None
          :raises: None