Mix of spaces and tabs: Python allows you to use either tabs or spaces for indentation, but you can’t mix them in the same block of code. ... If you’re using tabs, make sure your editor is set to ...

The following example comes from the documentation of xlsxwriter: import xlsxwriter workbook = xlsxwriter.Workbook('tab_colors.xlsx') # Set up some worksheets. worksheet1 = workbook.add_worksheet() ...