when i group by in pandas it doesn't group rows code example

Example 1: group by pandas examples

>>> n_by_state = df.groupby("state")["state"].count()
>>> n_by_state.head(10)
state
AK     16
AL    206
AR    117
AS      2
AZ     48
CA    361
CO     90
CT    240
DC      2
DE     97
Name: last_name, dtype: int64

Example 2: pandas groupby

data.groupby('month', as_index=False).agg({"duration": "sum"})