Why the download version is different with the online version?

[yaoerqin]

Hello there,

I'm a phD student right now and really interested in this project. I tried the action like this:
"git clone https://github.com/SizheAn/MARS.git" or directly download the project and unzip, the "MARS_model.py" file is not complete. The "import section" is blank.

Is there any problem of my operation?

Thank you.
Huimin YAO