group by with multiple columns aggregate min on one code example

Example 1: pandas sum multiple columns groupby

df.groupby(['col1','col2']).agg({'col3':'sum','col4':'sum'}).reset_index()

Example 2: group by 2 columns pandas

In [11]: df.groupby(['col5', 'col2']).size()
Out[11]:
col5  col2
1     A       1
      D       3
2     B       2
3     A       3
      C       1
4     B       1
5     B       2
6     B       1
dtype: int64