plasTeX 3.0 — A Python Framework for Processing LaTeX Documents

B.1.2 How can I get plasTeX to find my LaTeX packages?

There are two types of packages that can be loaded by plasTeX: 1) native LaTeX packages, and 2) packages written entirely in Python. plasTeX first looks for packages written in Python. Packages such as this are written specifically for plasTeX and will yield better parsing performance as well as better looking output. If you have a true LaTeX package, plasTeX will try to locate it using the kpsewhich program just like LaTeX does. For more information about packages, see the section 4.3.