text_html_output_1.png
import pandas as pd # data processing, CSV file I/O (e.g. pd.read_csv)

air = pd.read_csv('../input/air_reserve.csv')

airvisit = pd.read_csv('../input/air_visit_data.csv')
airvisit['visit_date'] = pd.to_datetime(airvisit['visit_date']).dt.date

len(airvisit['air_store_id'].unique())