IMO, this kata is salvagable so I'll publish a new one and see how community reacts! (Since author long gone)

Very unlikely case, did not consider that. Fixed

The question specifically states that the input may be uppercase or lowercase

I was not aware that conversion between hex and integers needed an additional explanation, especially as they are built-in features of python.
I recommend searching for it online or checking out the Wikipedia page if you are unsure https://en.wikipedia.org/wiki/Hexadecimal

But why for _ in range(3) instead of just random.randrange(16**6)?..

Input: #63fdba, Percentage = 79.3
Expected: #153427 or #143426 but got #143427

Random test input is in lowercase, but it's uppercase in the description and fixed tests.

You didn't even tell us how we are supposed to convert? What kind of kata is this lmao?

Your suggestion throws an error, I changed it to the following:
hexstring = "#" + "".join("%02x" % random.randrange(256) for _ in range(3))

and now it works
Thanks :)

random.randrange(16**6 - 1)

You're generating values from 000000 to FFFFFE.

hexvalue = "%x" % random.randrange(16**6 -1); hexstring = '#' + '0' * (6-len(hexvalue)) + hexvalue

This really should have been hexstring = "#" + "".join(f"{hex(randrange(256)):02x}" for _ in range(3)).

My bad, fixed.
Thanks for helping!

I missed the "not"... The values should NOT be limited to that range.

I presume he means the Red part of RGB with R.
However, the randrange function already guarantees values between #10 and #F as 16**5 + 1 is #100001 and 16**6 - 1 is #ffffff
(Feel free to reopen issue if I misunderstood you in any way)

Good idea, issue has been fixed