input: Write a function to determine if the first string contains the second string. If the first string contains the second string, return True; otherwise, return False. If the second string is empty, return True.
  assert check_contains("catering", "cat")==True
  assert check_contains("catering", "dog")==False
  assert check_contains("example", "")==True
  assert check_contains("", "word")==False
  assert check_contains("", "")==True
output: def check_contains(first, second):
      if second == "":
          return True
      return second in first