input: Write a python function to encrypt a message by replacing each character with a randomly chosen letter from the alphabet.
  assert len(encryptMessage("HELLO")) == 5
  assert encryptMessage("PYTHON").isupper()
  assert len(set(encryptMessage("WORLD"))) <= 5
output: import random
  import string
  
  def encryptMessage(message):
      alphabet = string.ascii_uppercase
      encrypted_message = ''.join(random.choice(alphabet) for _ in message)
      return encrypted_message