marshal
The marshal module is an alternate method to implement Python object serialization. It allows you to read/write information in a binary format, and convert data to/from character strings. Basically, it is just another way to do byte stream conversions by using serialized Python objects. It is also worth mentioning that marshal is used to serialize code objects for the .pyc files.
This module should be used for simple objects only. Use the pickle module to implement persistent objects in general.
See Chapter 8 for details.