Python as a programming language is just a tool to develop your solutions and therefore your question is too broad. You can simply use google to find various references...

https://github.com/jpn--/python-for-transportation-modeling

https://www.davidabailey.com/articles/Creating-a-Four-step-Transportation-Model-in-Python

Article Open Source Tools for Geographic Analysis in Transport Planning

Abolghasem Sagha

These links might help further, have a look:

1. https://towardsdatascience.com/tagged/transportation-planning

2. https://towardsdatascience.com/road-transportation-optimization-with-python-part-1-visualisation-costing-698eadcdce0b

3. https://github.com/topics/transportation-planning

4. https://github.com/tumluliu/pymmrouting

5. https://github.com/Robinlovelace/open-gat

6. https://github.com/bstabler/TransportationNetworks

7. https://github.com/jpn--/python-for-transportation-modeling

You may also consider using QGis as your GIS framework for your Python developments.

You can use python script to build a tool using ArcGIS For developing your model.

Python coding can be used to develop various tolls or software in Transportation plannings.

There are softwares like ArcGIS, which directly supports python coding within them. Link of my study that utilizes python in development of a tool for pavement maintenance planning is as follows:

https://www.researchgate.net/publication/351892654_Condition_Based_Maintenance_Planning_of_low_volume_rural_roads_using_GIS

This research can assist you.

yes, You can use python script to build a tool using ArcGIS For developing your model.