First, let's define the names of the variables that we are going to use in this analysis. We have a list of the numerical variables and a list of the categorical variables. Then, we will redefine our housing DataFrame with a DataFrame that contains only the variables that we just defined. Then, we use the shape attribute to see the size of the new DataFrame:
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In the preceding diagram, we can see that the shape of our DataFrame has now changed because we have only 15 columns.