Write a code block to encode strings into a secret message. Your code will presume a number, stored in key, and a message to encode, stored as a string variable called message. Don't define these variables in your code - they will be defined when you run the tests.

To do so:
Initialize a variable called encoded as an empty string
Use a for loop to loop across all characters of a string variable message
Inside the loop, convert the character to another character:
Get the unicode code point for the character (using ord)
Add the value of key to that code point (which should be an int)
Convert this new int back to a character (using chr).
Also inside the loop, add this converted char to the string encoded