W3School TIY Editor

import pandas as pd jan = pd.date_range(start='2021-01-01', end='2021-01-31') data = { "registered": [5, 4, 3, 4, 3, 5, 1, 6, 1, 9, 5, 3, 7, 2, 8, 4, 4, 6, 4, 3, 2, 5, 3, 4, 2, 6, 8, 5, 3, 4, 5] } df = pd.DataFrame(data, index=jan) print(df.first('5D'))