I want to use %-style string formatting to print a tuple: tup = (1,2,3) print("this is a tuple: %s." % (tup)) I expect it to print like This is a tuple: (1,2,3)., but instead I get an error that says TypeError: not all arguments converted during string formatting. What is wrong, and how do I fix it? In editing this question for clarity and modernization, I preserved one interesting aspect of the o