code: async def update_flags(self, selected: SelectedMailbox,
                             sequence_set: SequenceSet,
                             flag_set: FrozenSet[Flag],
                             mode: FlagOp = FlagOp.REPLACE) \
              -> Tuple[Iterable[Tuple[int, MessageInterface]], SelectedMailbox]:
          
          ...
docs: Update the flags for the given set of messages.
  
          See Also:
              `RFC 3501 6.4.6.
              <https://tools.ietf.org/html/rfc3501#section-6.4.6>`_
  
          Args:
              selected: The selected mailbox session.
              sequence_set: Sequence set of message sequences or UIDs.
              flag_set: Set of flags to update.
              mode: Update mode for the flag set.
  
          Raises:
              :class:`~pymap.exceptions.MailboxNotFound`
              :class:`~pymap.exceptions.MailboxReadOnly`