input: Write a function to combine 2 given strings and reverse the result in Python. The function `reverse_combine_strings` takes two parameters: `string_1` and `string_2`. It concatenates both strings and reverses the combined string, then returns the result.
  assert reverse_combine_strings("Hello ", "world!") == "!dlrow olleH"
  assert reverse_combine_strings("abc", "def") == "fedcba"
  assert reverse_combine_strings("", "123") == "321"
  assert reverse_combine_strings("Stay ", "positive!") == "!evitisop yaSt"
output: def reverse_combine_strings(string_1, string_2):
      combined = string_1 + string_2
      return combined[::-1]