Its 100% not your fault, your code is completely valid but the test is not robust enough, it is expecting you to concatenate at the end of the current existing line:
I assumed all that jargon was the aftermath of debugging. plus was trying to be a little encouraging and relieve any frustration from unexpected test behaviors.
It is great that you solved the challenge, but instead of posting your full working solution, it is best to stay focused on answering the original poster’s question(s) and help guide them with hints and suggestions to solve their own issues with the challenge. How to Help Someone with Their Code Using the Socratic Method
We are trying to cut back on the number of spoiler solutions found on the forum and instead focus on helping other campers with their questions and definitely not posting full working solutions.