Building packages is considered good coding practice since it allows for writing modular code and reuse. Modular code is code that is written in many smaller pieces for more pervasive use, without needing to know the underlying implementation details of everything involved in a task. For example, when we use matplotlib to plot something, we don't need to know what the code inside the functions we call is doing exactly—it suffices to simply know what the input and output will be to build on top of it.
Building a Python package
Package structure
A module is a single file of Python code that can be imported; window_calc.py from Chapter 4, Aggregating Pandas DataFrames, and color_utils.py from Chapter 6, Plotting with...