input: Write a function to encrypt a message using a Caesar cipher. The function should take two parameters: the message and the shift value. It should return the encrypted message.
  assert caesar_encrypt("Hello, World!", 3) == "Khoor/#Zruog$"
  assert caesar_encrypt("Python", 5) == "Udymts"
  assert caesar_encrypt("Goodbye", 2) == "Iqqfda"
  assert caesar_encrypt("", 3) == ""
output: def caesar_encrypt(message, shift):
      encrypted_message = ""
      for char in message:
          if char.isalpha():
              shift_amount = shift % 26
              if char.islower():
                  new_char = chr((ord(char) - ord('a') + shift_amount) % 26 + ord('a'))
              else:
                  new_char = chr((ord(char) - ord('A') + shift_amount) % 26 + ord('A'))
              encrypted_message += new_char
          else:
              encrypted_message += char
      return encrypted_message