Let's perform a combined exploration of both types of dataframes. Do you remember how we can merge dataframes? If not, I highly recommend pausing here and quickly skimming through Chapter 6, Grouping Datasets:

1. Let's see how we can concatenate both dataframes:

df_wines = pd.concat([df_red, df_white])

2. Let's also re-shuffle the rows so that it randomizes the data points:

df_wines = df_wines.sample(frac=1.0, random_state=42).reset_index(drop=True)

Note that the drop=True argument resets the indexes to the default integer index.

3. Next, we would like to check the first few columns to see whether all of the rows are correctly merged:

df_wines.head()

The output of the preceding code is given as follows:

Note that in Figure 12.10, we have correctly populated the columns, wine_category and quality_label.