stringfunc.py

import unittest
import sys


class Solution:
    def merge(self, original, add, delete):
        #Merge original and add in new string
        out = original + add
        #delete string
        for x in delete:
            for y in out:
                if (id(x) == id(y)):
                    out.remove(y)         
        
        #remove duplicates
        out = list(set(out))
        #sort reverse - also implicitly sorts alphabetical
        out.sort(reverse=True)
        return out



class Tests(unittest.TestCase):

    
    def test_1(self):
        out = ['thref', 'three', 'six', 'one']
        original = ['one', 'two', 'three']
        add = ['one', 'two', 'five', 'six','thref']
        delete = ['two', 'five']
        test1 = Solution()
        self.assertEqual(test1.merge(original,add,delete),out)


if __name__ == '__main__':
    unittest.main()