How to make custom Exception class

exception.py

'''
  Ref blog
    - https://www.programiz.com/python-programming/user-defined-exception
    - https://stackoverflow.com/questions/1319615/proper-way-to-declare-custom-exceptions-in-modern-python
'''

# Basic use
class CustomError(Exception):
    pass

raise CustomError("TEst")


# how it actually works
class Error(Exception):
    def __init__(self, message):
        super(Error, self).__init__(message)

class ValueTooSmallError(Error):
    pass

class ValueTooLargeError(Error):
    pass


number = 10

while True:
    try:
        i_num = int(input("Enter a number: "))
        if i_num < number:
            raise ValueTooSmallError("This value is too small, try again!")
        elif i_num > number:
            raise ValueTooLargeError("This value is too Large, try again!")
        break
    except Exception as e:
        print(e)