Calling Python from Excel using xlwings

You have three options to call Python from Excel using xlwings:

• The Run button under the xlwings tab of the ribbon
• Macros: These call Python from Excel
• User Defined Functions (UDFs) (Windows only)

Let’s have a look at the pros and cons of all three, as well as an example!

The Run button

The Run button expects a function called main in a Python module with the same name as your workbook. This is a quote from the documentation and a hard prerequisite. The main benefit of this method is that there is no VBA and no macros; you can use a normal XLSX file, which can be very useful in security-restricted situations where XLSM files are not allowed.

To try out the Run button, follow these steps:

1. Create a Python module called sumitup.py with the following code:

   import xlwings as xw
   def main():
               wb = xw.Book.caller()
      &...