def MessageSetItemEncoder(field_number):
  """Encoder for extensions of MessageSet.

  The message set message looks like this:
    message MessageSet {
      repeated group Item = 1 {
        required int32 type_id = 2;
        required string message = 3;
      }
    }
  """
  start_bytes = b"".join([
      TagBytes(1, wire_format.WIRETYPE_START_GROUP),
      TagBytes(2, wire_format.WIRETYPE_VARINT),
      _VarintBytes(field_number),
      TagBytes(3, wire_format.WIRETYPE_LENGTH_DELIMITED)])
  end_bytes = TagBytes(1, wire_format.WIRETYPE_END_GROUP)
  local_EncodeVarint = _EncodeVarint

  def EncodeField(write, value, deterministic):
    write(start_bytes)
    local_EncodeVarint(write, value.ByteSize(), deterministic)
    value._InternalSerialize(write, deterministic)
    return write(end_bytes)

  return EncodeField
Encoder for extensions of MessageSet.

  The message set message looks like this:
    message MessageSet {
      repeated group Item = 1 {
        required int32 type_id = 2;
        required string message = 3;
      }
    }
  
deps/protobuf/python/google/protobuf/internal/encoder.py