When I try to run the scripts in Jupyter Notebook for the Urban Growth Model, I get an error having to do with the UrbanCell class--see the screenshot:

I ran the space.py text first in Jupyter; then when I tried to import parts of the model script, and %run UrbanGrowthSpace.ipynb, it threw an error. Is this because the class name shares a name with one of the attributes?

I really appreciate any help you can provide. Sorry if this is confusing.