Group and sum values

Question

I have this df

'Item'   'Units Sold'

Item1      1
Item2      3
Item3      10
Item1      2
Item3      4

Then I want to group by item and sum the sold units:

Item   

'Item'   'Units Sold'

Item1      3
Item2      3
Item3      14

Answer 1

Use Groupby.sum():

In [1167]: df = df.groupby('Item', as_index=False).sum()

In [1168]: df
Out[1168]: 
    Item  Units_Sold
0  Item1           3
1  Item2           3
2  Item3          14