Python使用Excel将数据写入多个sheet

import pandas as pd
df1 = pd.DataFrame({'a':[3,1],'b':[4,3]}) 
df2 = df1.copy()
with pd.ExcelWriter('F:\\python入门\\数据2\\output.xlsx') as writer:
  str1 = ['a','b','c','d','e','f','g','h','i',\
      'j','k','l','m','n','o','p','q']
  for i in str1:
    name = str(i)
    df1.to_excel(writer, sheet_name= name)
writer.save()
writer.close()