Repeating values in a "group by" pandas dataframe

Question

I have the following pandas DataFrame:

     email   cat  class_price
0   [email protected]  cat1            1
1   [email protected]  cat2            2
2   [email protected]  cat2            4
3   [email protected]  cat2            4
4   [email protected]  cat2            1
5   [email protected]  cat1            3
6   [email protected]  cat1            2
7   [email protected]  cat2            1
8   [email protected]  cat2            4
9   [email protected]  cat2            2
10  [email protected]  cat3            1
11  [email protected]  cat1            1

And I want to group by email and by class_price, for each line I want to take the max of class_price.

I'm using:

test_df2 = test_df.groupby(['email','cat'])['class_price'].max()

The output is:

email             cat 
[email protected]  cat1    2
                  cat2    4
[email protected]  cat2    2
                  cat3    1
[email protected]  cat1    3
                  cat2    4

But how can I get a result where even grouped columns retain repeated values,such that it can be be written as a proper table with all the values:

email             cat      maxvalue 
[email protected]    cat2     2
[email protected]    cat1     2
[email protected]    cat3     3

Note: example output isn't compatible with example input just written to explain the idea.

Answer 1

You can try reset_index as in other answer or you can try below -

test_df2 = test_df.groupby(['email','cat'], as_index=False)['class_price'].max()