'''
Example from 
https://www.programiz.com/python-programming/user-defined-exception

by Xiannong Meng
2017-07-27
'''
'''
# define Python user-defined exceptions
class Error(Exception):
   """Base class for other exceptions"""
   pass

class ValueTooSmallError(Error):
   """Raised when the input value is too small"""
   pass

class ValueTooLargeError(Error):
   """Raised when the input value is too large"""
   pass
'''

class ValueTooSmallError(Exception):
   """Raised when the input value is too small"""
   #pass
   def __init__(self):
      self.__name__ = 'ValueTooSmall'
      print(self)
      
   def __str__(self):
      return self.__name__

class ValueTooLargeError(Exception):
   """Raised when the input value is too large"""
   #pass
   def __init__(self):
      self.__name__ = 'ValueTooLarge'
      print(self)
      
   def __str__(self):
      return self.__name__   

# our main program
# user guesses a number until he/she gets it right

# you need to guess this number
number = 10

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

print("Congratulations! You guessed it correctly.")