You forgot the closing quote at the end of the string. It should be f'string', but the final ' is missing.
Also, instead of hardcoding the result, you should use variables. For example, don’t write [John Doe]; use {full_name} instead.
I updated your post above so the code formats correctly on the forum.
There are two ways you can format your code to make it easier to read and test:
After you copy/paste your code into the editor, select it by dragging your cursor over it then click the (</>) button in the toolbar to automatically wrap your code in backticks. (You can click on the animated demo image below to enlarge it.)
Manually add three backticks on a new line above your code and on a new line after your code. Note that a backtick is NOT the same as a single quote('). To find the backtick key on your keyboard, see this post.
To see changes to your post as you make them, you can click the (M+) button on the toolbar to bring up the rich text editor:
It looks like you may have changed the starting code in areas you were not asked to change, which will cause the tests to fail. Please click the reset button to restore the original code and try again.