import pandas as pd

import datetime as dt

df = pd.DataFrame({"Date": ["2021/01/01","2021/01/01","2021/01/02"], "Time": ["22:00:00","23:00:00","00:00:00"]})

df["Date"] = pd.to_datetime(df["Date"])

df.info()

def trade_date(convert):

    for x in convert:

        if x == "23:00:00":

            return df["Date"] + pd.DateOffset(days=1)

        else: 

            return df["Date"] 

#df["Tradedate"] = df["Time"].apply(trade_date)

df["Tradedate"] = trade_date(df["Time"])

#trade_date(df["Time"])

df["Date"] = pd.to_datetime(df["Date"])

def trade_date(row):

    if row["Time"] == "23:00:00":

        return (row["Date"] + pd.DateOffset(days=1)).strftime('%Y/%m/%d')

    else:

        return row["Date"].strftime('%Y/%m/%d')

df["Tradedate"] = df.apply(trade_date, axis=1)

df["Date"] = df["Date"].dt.strftime('%Y/%m/%d')

print(df)

        Date      Time   Tradedate

0  2021/01/01  22:00:00  2021/01/01

1  2021/01/01  23:00:00  2021/01/02

2  2021/01/02  00:00:00  2021/01/02