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Python Python Basics (2015) Python Data Types String Formatting

Posted by Bill Jones
Bill Jones
346 Points

Why is my .format usage incorrect?

I am trying to learn how do use the .format with a string in Python. The current task instructs me to do the following:

"OK, now use .format() on the string "Treehouse loves {}" to put your name into the placeholder. Assign this to the variable subject (so start with subject =). You do not need to print() anything."

I get the following error message:

" Bummer! Be sure to use the {} placeholder and the .format() method."

Yet, I am doing both. When I try this in the workspace, it works.

strings.py 
name = "William F. Jones"
subject = "Treehouse loves {}"
subject.format(name)
louis coleman
louis coleman
1,753 Points
louis coleman
louis coleman
1,753 Points

Your .format function looks fine, however you are missing a print function. Try print(subject.format(name))

Jason Anders
Jason Anders
Treehouse Moderator 145,860 Points
Jason Anders
Jason Anders
Treehouse Moderator 145,860 Points

Hi there, louis coleman,

The challenge explicitly says not to print anything. So, adding a print will cause another error. The problem is how the format method is being applied. Supplied answer is below.

1 Answer

Jason Anders
MOD
Jason Anders
Treehouse Moderator 145,860 Points
Jason Anders
Jason Anders
Treehouse Moderator 145,860 Points

Hey Bill,

Challenges are very strict in how it checks your code, so instructions need to be followed exactly in order for the checker to pass you.

Here, the instructions specifically say to

use .format() on the string "Treehouse loves {}"

Note the key phrase "on the string" ... you are using it on the variable.

So, instead of two lines of code, the challenge is looking for the DRYer way of just one line.

subject = "Treehouse loves {}".format(name)

Hope that helps. :)

Keep Coding! :dizzy:

Bill Jones
Bill Jones
346 Points

Thank you. I actually considered that approach, but rejected it. While in the long, distant past I was proud of writing tight (DRY - new term for me) code, I didn't think combining the two lines in this case provided any advantage, and in fact would be problematic for the intended usage (email subject line generator). Admittedly, I've been out of technology for almost two decades and it's been three since I've moved code to prod - so I have a lot to learn. I'll look for those contextual clues on the challenges in the future.