Don't use input as paramenter name in Python - it's a builtin function to read keyboard inputs! Please rename it to data or something like that.

Please use a fixed-width font for the output window. Currently, it is extremely hard or impossible to e.g. see multiple spaces in an output string for debugging, except if I replace them e.g. with dots before printing.

The Python unit tests are wrong!
You have to type:

test.assert_equals(rot13("test"),"grfg")
test.assert_equals(rot13("Test"),"Grfg")

instead of:

test.assert_equals(rot13("test","grfg"))
test.assert_equals(rot13("Test","Grfg"))

And your final python test cases are not well designed. It depends on the import string statement in the solution code, which I tried to replace with a from string import ... that lead to the failing of your tests.

Would be nice if you could predefine and include the dictionary in the test environment, so that we don't have to copy it to the solution code.

No, I think it isn't. Either my solution is wrong (then please point the error out to me) or try< to correct/clarify your tests. I otherwise get errors like "0L should equal 0.0023766928765123672876" or something like that...

I am not very happy with the description for Python. You should write a separate one for this as it is very confusing that you call your custom class List while there is the builtin list, which equals your array you want returned.

Your test cases are full of spelling mistakes... Like ---"dectionary"--- instead of "dictionary", ---"undifined"--- instead of "undefined", etc. And [] is not called "Array" but "List" in Python.

Unfortunately, I forgot to remove the print statement for debugging before hitting on "Final Submit"... >.<

Yes, some time after having posted this, I saw that I missed a closing bracket somewhere in my code... I am sorry.

The unit tests fail:

File "", line 8
    Test.assert_equals(mixed_fraction('42/9'), '4 2/3')
       ^
SyntaxError: invalid syntax

You should really improve the description. One can only find out from the test cases that you expect the function to return a dictionary with the elements of the array as keys and their number as values.

I would make the description about the output for a given list of multiple names more clear. One could also think to return a concatenated string instead of a list of strings.