input: Write a function to search a given input string in a list of strings using regular expressions. If a match is found, return "String matches", otherwise return "String doesn't match".
  assert search_string_in_list(["First","Second","Third"], "Second")=="String matches"
  assert search_string_in_list(["First","Second","Third"], "Fourth")=="String doesn't match"
  assert search_string_in_list(["First","Second","Third"], "rst")=="String matches"
  assert search_string_in_list(["First","Second","Third"], "XYZ")=="String doesn't match"
  assert search_string_in_list(["First","Second","Third"], "")=="String doesn't match"
output: import re
  
  def search_string_in_list(string_list, input_string):
      for s in string_list:
          if re.search(input_string, s):
              return "String matches"
      return "String doesn't match"