Create new exception in python

Question

class RuntimeError(Exception):
def __init__(self, mismatch):
Exception.__init__(self, mismatch)
try:
print ("And now, the Vocational Guidance Counsellor Sketch.")
raise RuntimeError("Does not have proper hat")
print ("This print statement will not be reached.")
except RuntimeError as problem:
print ("Vocation problem: {0}".format(problem))

Can u guys help me with this
I find this so difficult to understand
In line Exception.__init__(self, mismatch) that i can't clearly understand that

Answer 1

What you actually doing in here is inheriting from the Exception class. This allows you to make your own user-defined exception. And then the constructor for the user defined exception is defined. And the line

Exception.__init__(self, mismatch)

calls the __init__ method (constructor) for the Exception class, because when you define a constructor in a Child class (class which inherits), it overrides the __init__ method of the Base class.

(If you did not understand what I said, please go through the course here once again (or complete it if you haven't))

Answer 2

Tks a lot your answer XXX it's very helpful