input: Write a python function to generate a random password of a given length.
  assert len(random_password_generator(8)) == 8
  assert len(random_password_generator(12)) == 12
  assert len(random_password_generator(16)) == 16
output: import random
  import string
  
  def random_password_generator(length):
      characters = string.ascii_letters + string.digits + string.punctuation
      password = ''.join(random.choice(characters) for _ in range(length))
      return password