Prove that the set of Python strings is countable by defining a well documented Python function from strings to natural numbers, and proving that your function is an injection.

This assignment will receive from 0 to 3 points of extra credit on the final exam, depending on quality. Each function in your program should have a clear and precise function header (i.e., documentation), that includes sample inputs with their corresponding outputs. In addition, the program header (documentation at the top of the page) should demonstrate convincingly that the top level function is an injection, in such a way that a reasonably prepared fellow student could read it and be convinced.

Your function should be in a single file, titled .py, for example JohnSmith.py