helpers.py module not in sys.path

helpers.py module is not accessible if it's in the "text-analysis/code" directory unless either...

1) the code directory is added to sys path e.g. `sys.path.insert(0, '/content/drive/My Drive/Colab Notebooks/text-analysis/code')`

2) helpers.py is moved from the code directory into the text-analysis dir.

This is an optional method used first here:

https://carpentries-incubator.github.io/python-text-analysis/03-preprocessing/index.html#loading-data-into-python