python series groupby count code example
Example 1: groupby count pandas
df.groupby(['col1', 'col2']).size()
Example 2: group by pandas count
df[['col1', 'col2', 'col3', 'col4']].groupby(['col1', 'col2']).agg(['mean', 'count'])
df.groupby(['col1', 'col2']).size()
df[['col1', 'col2', 'col3', 'col4']].groupby(['col1', 'col2']).agg(['mean', 'count'])