Forked and approved

LGTM, approved

Take a look at the comments in solution setup: you are not meant to allocate any memory, but you are expected to use the doubled buffer and write your answer into it, and then return the doubled.

Your solution is almost correct, you just should write to doubled without malloc-ing it.

A great little exercise.

my bad. thanks for your time. I am n3wb.

You are using the wrong function name. Should be double_char whilst yours is repeat_each_letter

I am getting this error

Traceback (most recent call last):
File "/workspace/default/tests.py", line 2, in
from solution import double_char
ImportError: cannot import name 'double_char' from 'solution' (/workspace/default/solution.py)

C++ Translation

Thank you so much hobovsky and Chrono79, I was trying to print the output causing the test to fail, it passed now after making the required changes

Read this too: https://docs.codewars.com/training/troubleshooting#post-discourse

Your solution is not exactly correct, it gets one small thing wrong. See this paragraph for some help.

It is not a kata issue.

i finished the first bit but now i cant do the 2 other ones
:(

Your code is incorrect and it does not work.

Additionally, remember that reporting posts of users who are pointing out your mistakes is not a right thing to do. It's abuse of moderation mechanisms and is disruptive for work of moderators, who are forced to review such unreasonable reports. Don't do this.