code: function wrapper(type, contents) {
      var buf, len, i;
  
      // Get the encoded length of the contents
      len = lengthArray(contents.length);
  
      // Set up a buffer with the type and length bytes plus a straight copy of the content.
      buf = new Buffer(1 + contents.length + len.length);
      buf[0] = type;
      for (i = 1; i < len.length + 1; i++) {
          buf[i] = len[i - 1];
      }
      contents.copy(buf, len.length + 1, 0);
      return buf;
  }
docs: Return a wrapped copy of the passed `contents`, with the specified wrapper type. This is used for Sequence and other constructed types.