几只股票的开始日期不同

Question

我正在尝试构建自己的投资组合报告，以跟踪过去在不同日期购买的不同股票-以下是代码，但出现以下错误： ValueError：时间数据“ AMZN_start”与格式“％Y-％m-％d”不匹配

import pandas as pd
import yfinance as yf
import datetime as dt
import seaborn as sns
import matplotlib.pyplot as plt
from matplotlib import style

TempDF = pd.DataFrame() # 2020-11-09
# getting stock ticker
tickers = ['AMZN','NVDA']
starts = ['2016-08-26','2020-03-24'] # update 2020-11-9
end = dt.datetime.today()

# Ticker to download update:2020-11-9
for ticker,start in zip(tickers, starts): 
    data = yf.download(ticker, start, end, interval="1d")
    TempDF = TempDF.append(data) # update 2020-11-09

# Creating DF and adding metrics
#TempDF = pd.DataFrame(data)

TempDF.drop(TempDF.columns[[0,1,2,3,5]], axis=1, inplace=True)

TempDF['DailyReturn'] = TempDF['Adj Close'].pct_change()
TempDF.fillna(method='bfill', inplace=True)