Using groupby on already grouped data in Pandas

I would like to achieve the result below in Python using Pandas.

I tried groupby and sum on the id and Group columns using the below:

df.groupby(['id','Group'])['Total'].sum()

I got the first two columns, but I’m not sure how to get the third column (Overall_Total).

How can I do it?

Initial data (before grouping)

id	Group	Time
1	a	2
1	a	2
1	a	1
1	b	1
1	b	1
1	c	1
2	e	2
2	a	4
2	e	1
2	a	5
3	c	1
3	e	4
3	a	3
3	e	4
3	a	2
3	h	4

Answer

Assuming df is your initial dataframe, please try this:

df_group = df.groupby(['id','group']).sum(['time']).rename(columns={'time':'Total'})
df_group['All_total'] = df_group.groupby(['id'])['Total'].transform('sum')