似乎您正在遇到一些范围界定问题.避免此问题的一种方法是使用列表理解.您还可以使用pd.DataFrame.assign在列表理解范围内添加系列:

Seems like you are meeting some scoping issues. One way to avoid this problem is to use a list comprehension. You can also use pd.DataFrame.assign to add a series within your list comprehension:

dfList = [pd.read_excel(infile, sheet_name, header=0).assign(Well_name=sheet_name) \
          for sheet_name in xls.sheet_names()]

dfs = pd.concat(dfList, axis=0)