Replace xlsx by OpenPyXL
This library currently has no active maintainers. You are advised to use OpenPyXL instead. If you absolutely have to read .xls files, then xlrd will probably still work for you, but please do not submit issues complaining that this library will not read your corrupted or non-standard file. Just because Excel or some other piece of software opens your file does not mean it is a valid xls file.
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