Aggregate with sum

You will deal with an aggregation feature, agg_with_sum(). As you know, pd.DataFrame.groupby() returns a new dataset by aggregating the initial one with some function, in this case - .sum(). But the important thing is that you want to verify it works properly.

Let's assume you know nothing about the data, but you know for sure that agg_with_sum() returns pd.Series. It is also reasonable to assume that the pd.Series will not be empty, and it will also contain some numeric values since it was processed with .sum().