input: Below is an instruction that describes a task. Write a response that appropriately completes the request.
  
  ### Instruction:
  Write a Python function to reverse a string using recursion.
  
  ### Input:
  
  
  ### Output:
  def reverse_string(s: str) -> str:
      """ Recursively reverse a string.
      >>> reverse_string("hello")
      'olleh'
      >>> reverse_string("12345")
      '54321'
      >>> reverse_string("")
      ''
      """
      if not s:
          return s
      else:
          return reverse_string(s[1:]) + s[0]
  
  print(reverse_string("example"))
output:     if not s:
          return s
      else:
          return reverse_string(s[1:]) + s[0]