text: """Custom exceptions"""
  
  class CustomException(Exception):
      """This class defines and abstract exception class so that customized exceptions
      can be inherited."""
  
      def __init__(self, value):
          """doc"""
          self.value = value
  
      def __str__(self):
          """Returning the error message"""
          return repr(self.value)
  
  
  class Tankoh2Error(CustomException):
      """classdocs"""
  
  
  