code: def readMultiByte(self, length, charset):
          
          #FIXME nick: how to work out the code point byte size (on the fly)?
          bytes = self.stream.read(length)
  
          return unicode(bytes, charset)
docs: Reads a multibyte string of specified length from the data stream
          using the specified character set.
  
          @type length: C{int}
          @param length: The number of bytes from the data stream to read.
          @type charset: C{str}
          @param charset: The string denoting the character set to use.
  
          @rtype: C{str}
          @return: UTF-8 encoded string.