Small challenge to find the best phone operator to use based on call price

• We'll be using Python as programing language as it is pretty straightforward to build a fast prototype of the solution, and also as it offers many libraries aimed at making large datasets manipulation easier (pandas, numpy, ...)

• We'll be using a Jupyter notebook in order to have a maximum of ergonomy and a beautiful visual presentation. Also, there will be no need to download or re-run the code as the results is already displayed in the notebook.

• Unit Testing will be done within the same notebook, in separated cells to show directly that everything runs as expected.

• In case we want to have a production-ready prototype that deals with larger datasets, one of the best choices I propose is to use Apache Spark with the Scala API, as it is especially aimed for Big Data, and because it runs on the JVM.

• $ git clone https://github.com/redouane-dev/cheapest-phone-call.git
• $ cd cheapest-phone-call
• Create a virtual environment to avoid dealing with dependency issues and conflicts : $ virtualenv -p python3 venv
• $ source ./venv/bin/activate. You'll start seeing a (venv) before the shell prompt.
• (venv) $ pip install -r requirements.txt in order to install all the requirements.

Now you should be all set to run the notebook

• (venv) $ jupyter notebook prototyping.ipynb