Something new that I learnt.

Wow. Learned so much!

You need to write regex

Do you know what regex means? It's short for regular expression. Google that. And in this kata you should only write the regex inside those quotes and nothing more.

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Well, your response sounds similar to this story:

I have been training for the mid exam, and last time I took a training quiz from the book I got 100. But in the exam, somehow I got 65. Well, I only trained for the first 3 chapters of the book but the teacher said the first 5 chapters are going to be included. Well, still I don't care. I got 100 in my quizes. There must be something wrong with the exam or the teacher themself!

Of course, the exam and the teacher is not to be blamed, but the person not trained or didn't dive deeper enough into the materials. This applies to what you have as well. To you it is fine in your machine, with your tests and what you think the strings would be. But deep down, strings can come in many forms that you haven't thought of and your regex failed to handle those said strings. Now, it is back to you whether you want to fix it or nah. The strings are shown to you in the tests. You can add those said failed strings to your local tests assertion.

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Why do you ask this question when your PP is the because?

Why do you think something is wrong with the kata, and not with your solution?

ive never used regex in my life eye opener

see here

Please read this: https://docs.codewars.com/training/troubleshooting#post-discourse and use code block formatting next time.

See the initial code, you only need to write a regular expression, not a function:

regex=""

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