  An easy way to define and visualize geometry for PHITS input files
introduced. Suggested FitsGeo Python package helps to define surfaces as Python
objects and manipulate them conveniently. VPython assists to view defined
geometry interactively which boosts geometry development and helps with
complicated cases. Every class that sets the surface object has methods with
some extra properties. As well as geometry generation for PHITS input,
additional modules developed for material and cell definition. Any user with a
very basic knowledge of Python can define the geometry in a convenient way and
use it in further research related to particle transport.
