I am missing one mark ,kindly assist me to fix the error since it's giving me an error and i have tried to fix it many times but still not succeeding

I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

You can also use the “preformatted text” tool in the editor (</>) to add backticks around text.

Pre-formatted-text

See this post to find the backtick on your keyboard.
Note: Backticks (`) are not single quotes (’).