input: Write a function to generate a random password consisting of 8 characters. Each password should include a mix of uppercase letters, lowercase letters, and digits.
  assert generate_password() != generate_password()
  random_password = generate_password()
  assert len(random_password) == 8
  assert any(c.isupper() for c in random_password)
  assert any(c.islower() for c in random_password)
  assert any(c.isdigit() for c in random_password)
output: import random
  import string
  
  def generate_password():
      characters = string.ascii_letters + string.digits
      return ''.join(random.choice(characters) for _ in range(8))