Add returns and assigns recursively

[JSAbrahams]

Relevant issues

• Was reminded of the fact that we don't have error handling properly implemented yet when added the function_with_try_except test. Created #374 as a result.
• More completely implemented #360 by making implementation recursive.

Summary

We go into the branches of relevant core modules. Only try except cannot be tested yet as we don't yet have error handling properly implemented.

• Also remove some redundant application logic

Added Tests

Happy

• return in if in function, and following within function:
• return in if nested in if
• returns in match