Now, let's take a look at the relationship between neighborhood and sale prices of the houses in our data set. Notice that currently we don't have the actual names for the neighborhoods. Instead we will use a similar column Neighborhood Code (which is a numerical encoding of the actual neighborhoods by the Assessment office). Part 1 Before creating any visualization, let's quickly inspect how many different neighborhoods we are dealing with. Assign the variable num_neighborhoods with the total number of neighborhoods in training_data . num_neighborhoods = I grader .check( "q6a")