How to use "raise" keyword in Python

Question

I have read the official definition of "raise", but I still don't quite understand what it does.

In simplest terms, what is "raise"?

Example usage would help.

Answer 1

It has two purposes.

jackcogdill has given the first one:

It's used for raising your own errors.

if something:
   raise Exception('My error!')

The second is to reraise the current exception in an exception handler, so that it can be handled further up the call stack.

try:
  generate_exception()
except SomeException as e:
  if not can_handle(e):
    raise
  handle_exception(e)