Calculate the variance manually

As a reminder, we use the following process to calculate the sample variance:

Let's calculate the sample variance of Michael Jordan's points per game!

The dataset data_jordan is loaded into your workspace.

Calculate the mean points per game and save the result to mean_ppg.
Subtract the mean points per game from the vector of points scored in each game and assign the result to diff.
Square this vector of differences and save to squared_diff.
Calculate the sample variance by summing the values in squared_diff with sum() and dividing by the sample size minus 1 using length() to count the number of games in the sample. Just print the result without saving it.
Check your result by calculating the variance with R's built-in var() function.