------
## 最终结论
```python
def encode(message):
    result = ''
    for char in message:
        # Swap case of the character
        char = char.swapcase()
        
        # Check if the character is a vowel and replace it
        if char.lower() in 'aeiou':
            char = chr(ord(char) + 2)
        
        # Add the processed character to the result
        result += char
    
    return result

# Examples
print(encode('test'))  # Output: 'TGST'
print(encode('This is a message'))  # Output: 'tHKS KS C MGSSCGG'
```