Problem 42441. Code Wheel

Create a function that offsets each value in a given string by a given amount.

For instance,

codewheel('hello',1) 

should output 'ifmmp'.

The output string should have the same punctuation, spacing, and capitalization as the input, so

codewheel('Hello, World!',3) 

should output 'Khoor, Zruog!'.