This is so cool, I love it.

nice use of strings.TrimRight

Still I would say that confusing stack trace is an issue with tests.

Thanks rowcased for your reply.
I just attempted once again and this time I passed all the tests. :)
I dont know about the initial value because the test values were not visible.
Have a good day.

The last line of your error message tells you the most. Print your inputs to see what you're dealing with there, probably an empty container... Do you know about the initial value referrred to about the reduce function?

I passed every other test, but only the last small test sends this eexception:
Is it my error?
Unexpected exception raised

Traceback (most recent call last):
File "/runner/frameworks/python/cw-2.py", line 111, in wrapper
func()
File "main.py", line 45, in small_tests
test.assert_equals(check(prime_factors(number), number), True)
File "main.py", line 34, in check
actual = reduce(lambda x, y: x*y, [i ** j for i, j in zip(primes, power)])
TypeError: reduce() of empty sequence with no initial value

Brilliant. Good job!

Good solution!
I agree that the spacing must have been more generous.