Pandas -count顾客在购买前访问商店的次数。(仅包括购买日期前30天的访问)

import pandas as pd

visits = pd.DataFrame({'customer_id': [1, 2, 3, 4, 5],
                       'visit_date': ['2022-01-01', '2022-01-02', '2022-01-03', '2022-01-04', '2022-01-05'],
                       'purchase_date': ['2022-01-05', '2022-01-03', '2022-01-04', '2022-01-05', '2022-01-05']})

visits['visit_date'] = pd.to_datetime(visits['visit_date'])
visits['purchase_date'] = pd.to_datetime(visits['purchase_date'])

visits['days_before_purchase'] = visits['purchase_date'] - visits['visit_date']
visits['days_before_purchase'] = visits['days_before_purchase'].dt.days
visits_within_30_days = visits[visits['days_before_purchase'] <= 30]
customer_visit_count = visits_within_30_days.groupby('customer_id').size()

print(customer_visit_count)