How to only validate file names with .xlsx extension?

Question

I have a Gooey based GUI where the user can input a name for the output file to be created at the end of the program. However, I would like to make it only possible to add file names with the .xlsx extension in the end.

This is the validator I have:

 parser.add_argument('-Choose_File_Name',
                        action='store',
                        help="Output File Name with .xlsx",
                         gooey_options={
                             'validator': {
                                 'test': 'str(user_input) == .xlsx',
                                 'message': 'Must contain .xlsx at the end!'
                                 }
                             })

However it gives me an invalid syntax error for the line 'test': 'str(user_input) == .xlsx'

Answer 1

Use str.endswith

Ex:

parser.add_argument('-Choose_File_Name',
                        action='store',
                        help="Output File Name with .xlsx",
                         gooey_options={
                             'validator': {
                                 'test': 'user_input.endswith(".xlsx") == True',
                                 'message': 'Must contain .xlsx at the end!'
                                 }
                             })