So simple yet not working....

[giladal]

In your changed version, on line 5: temperature.replace() doesn't modify temperature. It returns the modified string. If you don't assign it to something (like temperature), the replacement is lost.

temperature.replace("F", "") # this is a noop because the replaced string is not captured anywhere

BINGO! Now it works.
So now I understand that I can't just add the .replace to a str and it will replace the character. I have to assign it to the variable.

Thanks a million bowlofred!!