code: def clear_muc_child(self):
          
          if self.muc_child:
              self.muc_child.free_borrowed()
              self.muc_child=None
          if not self.xmlnode.children:
              return
          n=self.xmlnode.children
          while n:
              if n.name not in ("x","query"):
                  n=n.next
                  continue
              ns=n.ns()
              if not ns:
                  n=n.next
                  continue
              ns_uri=ns.getContent()
              if ns_uri in (MUC_NS,MUC_USER_NS,MUC_ADMIN_NS,MUC_OWNER_NS):
                  n.unlinkNode()
                  n.freeNode()
              n=n.next
docs: Remove the MUC specific stanza payload element.