in reply to
Set Background Color Using Spreadsheet::SaveParser
The get_format() in the first line returns a Spreadsheet::ParseExcel Format object which doesn't have a set_color() method, or set_anything() method since it is a read/information only object.
Possibly you are getting it confused with a Spreadsheet::WriteExcel format method that you have in the same program. If that is the case, then you will have to map the Spreadsheet::ParseExcel format properties to Spreadsheet::WriteExcel format properties, one by one.