  We introduce a new flexible one-dimensional photochemical model named
Photochemical and RadiatiOn Transport model for Extensive USe (PROTEUS), which
consists of a Python graphical user interface (GUI) program and Fortran 90
modules. PROTEUS is designed for adaptability to many planetary atmospheres,
for flexibility to deal with thousands of or more chemical reactions with high
efficiency, and for intuitive operation with GUI. Chemical reactions can be
easily implemented into the Python GUI program in a simple string format, and
users can intuitively select a planet and chemical reactions on GUI. Chemical
reactions selected on GUI are automatically analyzed by string parsing
functions in the Python GUI program, then applied to the Fortran 90 modules to
simulate with the selected chemical reactions on a selected planet. PROTEUS can
significantly save the time for those who need to develop a new photochemical
model; users just need to write chemical reactions in the Python GUI program
and just select them on GUI to run a new photochemical model.
