In Python how would you create exception and error handling $($for example, bad user input or resource allocation failures$)$ so that the application$/$server would continue to run and accept queries under all circumstances? $($Outside of physical server failure$)$

Ultimately, I am attempting to write a couple of programming guidelines for how a server$/$application should deal with these types of exceptions, but still allow the application to continue running & accepting queries.

Any input$/$advice$/$direction is appreciated.