Writing a computer program that will analyse the quality of another computer program?

I'm interested in knowing the possibilities of this. I'm working on a project that validates the skills of a software engineer, currently we validate skills based on code reviews by credentialed developers.

I know the answer if far more completed that the question, I couldn't imagine how complex the program would have to be able to analyse complex code but I am starting with basic programming interview questions.

For example, the classic FizzBuzz question:

Write a program that prints the numbers from 1 to 20. But for multiples of three print “Fizz” instead of the number and for the multiples of five print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz”.

and below is the solution in python:

for num in range(1,21):
    string = ""
    if num % 3 == 0:
        string = string + "Fizz"
    if num % 5 == 0:
        string = string + "Buzz"
    if num % 5 != 0 and num % 3 != 0:
        string = string + str(num)
    print(string)

Question is, can we programatically analyse the validity of this solution?

I would like to know if anyone has attempted this, and if there are current implementations I can take a look at. Also if anyone has used z3, and if it is something I can use to solve this problem.