docs: def resolve_id(marked_id):
      """Given a marked ID, returns the original ID and its :tl:`Peer` type."""
      if marked_id >= 0:
          return marked_id, types.PeerUser
  
      # There have been report of chat IDs being 10000xyz, which means their
      # marked version is -10000xyz, which in turn looks like a channel but
      # it becomes 00xyz (= xyz). Hence, we must assert that there are only
      # two zeroes.
      m = re.match(r'-100([^0]\d*)', str(marked_id))
      if m:
          return int(m.group(1)), types.PeerChannel
  
      return -marked_id, types.PeerChat