In [11]: air_quality["month"] = air_quality["datetime"].dt.month
In [12]: air_quality.head()
Out[12]:
city country datetime location parameter value unit month
0 Paris FR 2019-06-21 00:00:00+00:00 FR04014 no2 20.0 µg/m³ 6
1 Paris FR 2019-06-20 23:00:00+00:00 FR04014 no2 21.8 µg/m³ 6
2 Paris FR 2019-06-20 22:00:00+00:00 FR04014 no2 26.5 µg/m³ 6
3 Paris FR 2019-06-20 21:00:00+00:00 FR04014 no2 24.9 µg/m³ 6
4 Paris FR 2019-06-20 20:00:00+00:00 FR04014 no2 21.4 µg/m³ 6