The axes.prop_cycle rcParam accepts Python expressions that are evaluated
in a limited context. The evaluation context has been further limited and some
expressions that previously worked (list comprehensions, for example) no longer
will. This change is made without a deprecation period to improve security.
The previously documented cycler operations at
https://matplotlib.org/cycler/ are still supported.
This change was originally slated for v3.11.0 of Matplotlib, but was additionally backported due to the security implications.