The covariance is a widely used statistical estimate to measure how much a variable does vary when the other increase or decreases.
Here is an example of when you plot two variables.
The covariance is also used to compute the correlation between two variables.
The Pandas library provides the DataFrame.cov() method that will compute the covariance for you.
Here is the code
Here you are! You should be by now the king of covariance in Python!