input: Write a function called search_string that takes a string input from the user and searches a given list of strings to find any matches. If a match is found, print "String matches"; otherwise, print "String doesn't match". Ensure that the search is case-insensitive.
  
  import re
  
  def search_string(strings):
      inp_str = input("Please enter your string: ")
      found = False
      for i in strings:
          if re.search(i, inp_str, re.IGNORECASE):
              found = True
      if found:
          print("String matches")
      else:
          print("String doesn't match")
  
  assert search_string(["First", "Second", "Third"]) == None
  assert search_string(["apple", "banana", "cherry"]) == None
  assert search_string(["python", "Java", "C++"]) == None
  assert search_string(["cat", "dog", "elephant"]) == None
  assert search_string([]) == None
output: def search_string(strings):
      inp_str = input("Please enter your string: ")
      found = False
      for i in strings:
          if re.search(i, inp_str, re.IGNORECASE):
              found = True
      if found:
          print("String matches")
      else:
          print("String doesn't match")