我有这个数据框：
df = {'DATE': [43390, 43599, 43605, 43329, 43440],
'STORE': [1, 1, 1, 2, 2],
'LYLTY_CARD_NBR': [1000, 1307, 1343, 2373, 2426],
'TXN_ID': [1, 348, 383, 974, 1038],
'PROD_QTY': [2, 3, 2, 5, 3],
'TOT_SALES': [6.0, 6.3, 2.9, 15.0, 13.8]}
transac = pd.DataFrame(df)
DATE STORE LYLTY_CARD_NBR TXN_ID PROD_QTY TOT_SALES
0 43390 1 1000 1 2 6.0
1 43599 1 1307 348 3 6.3
2 43605 1 1343 383 2 2.9
3 43329 2 2373 974 5 15.0
4 43440 2 2426 …