code: def enqueue_mod(self, dn, mod):
          
          # mark for update
          if dn not in self.__pending_mod_dn__:
              self.__pending_mod_dn__.append(dn)
              self.__mod_queue__[dn] = []
  
          self.__mod_queue__[dn].append(mod)
docs: Enqueue a LDAP modification.
  
          Arguments:
          dn -- the distinguished name of the object to modify
          mod -- an ldap modfication entry to enqueue