input: Write a function to search for a character in a given string and return True if the character is found, otherwise return False. If the string is empty, return False.
  assert search_char("Hello", 'l')==True
  assert search_char("Hello", 'o')==True
  assert search_char("Hello", 'z')==False
  assert search_char("Hello", 'H')==True
  assert search_char("", 'l')==False
output: def search_char(s, char):
      if not s:
          return False
      return char in s