Trying to solve using Python3, one test passes (and every number I pass to my algorithm returns the correct prime factor decomposition with testing I've done outside of this kata), but then another fails with: '(2)' should equal '(7919)'

Can someone help explain to me what this might mean?

Using Python 2, for the test case:

Test.assert_equals(last_digit(2 ** 200, 2 ** 300), 6)

Locally, I get the correct answer returned, which is 6. But when I try in the editor here, I get:

Traceback: in <module> in last_digit TypeError: unsupported operand type(s) for ** or pow(): 'str' and 'str'

So many people have issues with timeout errors, re-write the test cases!
Like @paolo435 I just re-wrote my Python solution in JS, and it passed.

Using Python, upon submit, I'm getting:
✘ 4 should equal 2

Any idea what's going on? Is there a way to actually see the test cases being used?

I have a Python solution to this that works with any number I pass to it, but when I submit to this Kata, I'm getting this error:

✘ None should equal ' *\n***\n *\n'

What does this mean?

What's the deal with this Kata? All tests pass, except test for null array, where I get back:

✘ Must work with no names - Expected: , instead got: ,

What's the differnece between , and , ?

Oh looky here, another broken Kata....yay...
My solution passes all tests, except the last one, wherein the failed test result is:

✘ Expected: N ffns bt, Yr wrtng s mng th wrst 'v vr rd, instead got: Ths wbst s fr lsrs LL!N ffns bt, r wrtng s mng th wrst 'v vr rd

So apparently, the test isn't setup properly? When I actually pass the string it looks like it wants to be testing, it works. But this failed test result looks like extra text is being added.