Como criar minha própria exceção em Python

class MyException(Exception):
    pass

raise MyException("My hovercraft is full of eels")

"""With modern Python Exceptions, 
you don't need to abuse .message, or override .__str__() or .__repr__() 
or any of it. If all you want is an informative message when your 
exception is raised, do this
Adventurous Addax