[$] Insecurity and Python pickles

Serialization is the process of transforming Python objects into a sequence of
bytes which can be used to recreate a copy of the object later — or on another
machine.

pickle is Python's native serialization module. It can store complex Python
objects,
making it an appealing prospect for moving data without having to write
custom serialization code. For example, pickle is an integral component of
several file
formats used for machine learning. However, using pickle to deserialize
untrusted files is a major security risk, because doing so can invoke arbitrary
Python functions. Consequently, the machine-learning community is working to address the
security issues caused by widespread use of pickle.