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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def find_deleted(self, seq_set: SequenceSet, selected: SelectedMailbox) -> Sequence[int]: """Return all the active message UIDs that have the ``\\Deleted`` flag. Args: seq_set: The sequence set of the possible messages. selected: The selected mailbox session. """

        session_flags = selected.session_flags
        return [msg.uid async for _, msg in self.find(seq_set, selected)
                if Deleted in msg.get_flags(session_flags)]