code: def WriteVarBytes(self, value, endian="<"):
          
          length = len(value)
          self.WriteVarInt(length, endian)
  
          return self.WriteBytes(value, unhex=False)
docs: Write an integer value in a space saving way to the stream.
          Read more about variable size encoding here: http://docs.neo.org/en-us/node/network-protocol.html#convention
  
          Args:
              value (bytes):
              endian (str): specify the endianness. (Default) Little endian ('<'). Use '>' for big endian.
  
          Returns:
              int: the number of bytes written.