I have a dataframe that looks after using the pandas group function:
group. letters.  counts.   sum_1.    sum_2
1.     a.        20        3.        2
1.     b.        40.       2.        3
2.     a.        60.       3.        5
2.     b.        90.       5.        4
and I want to automate it without having to do it in Excel to make something like this: excel
group. letters.  counts.   sum_1.        sum_1_%.   sum_2.   sum_2rate
    1.     a.        20        3.        5%          2       3.33%
    1.     b.        40.       2.        3.33%       3       5%
    total.           60        5                     5
    2.     a.        60.       3.                    5
    2.     b.        90.       5.                    4
 
    