Here's a possible solution:

```
word = input("Enter a word: ")
shifted_word = ""
for letter in word:
    # Get the ASCII code of the current letter and add 2
    shifted_code = ord(letter) + 2
    # If the resulting code is greater than the ASCII code for 'z',
    # wrap around to 'a' and continue counting from there
    if shifted_code > ord('z'):
        shifted_code = ord('a') + (shifted_code - ord('z') - 1)
    # If the resulting code is greater than the ASCII code for 'Z'
    # but less than the ASCII code for 'a', wrap around to 'A' and continue
    # counting from there
    elif shifted_code > ord('Z') and shifted_code < ord('a'):
        shifted_code = ord('A') + (shifted_code - ord('Z') - 1)
    # If the resulting code is less than the ASCII code for 'A',
    # wrap around to 'a' and continue counting from there
    elif shifted_code < ord('A'):
        shifted_code = ord('a') + (shifted_code - ord('A'))
    # Convert the shifted code back to a character and add it to the shifted word
    shifted_word += chr(shifted_code)

print(f"The original word was '{word}' and the shifted word is '{shifted_word}'.")
```
Parola di input: mela
Genera un programma Python corretto per spostare tutte le lettere in una data parola di due caratteri avanti.