input: def generate_password():
      """ Generate a random password that consists of 8 characters including uppercase letters, lowercase letters and digits.
      >>> password = generate_password()
      >>> len(password)
      8
      """
      import string
      import random
      chars = string.ascii_letters + string.digits
      return ''.join(random.choice(chars) for _ in range(8))
output:     import string
      import random
      chars = string.ascii_letters + string.digits
      return ''.join(random.choice(chars) for _ in range(8))