class JunkComparisonException (BaseException):

	pass

class Junk:

	def __init__ (self):
		pass

	def __str__ (self):
		return "[Junk]"

	def __repr__ (self):
		return "[Junk]"

	def __add__ (self, other):
		return self

	def __radd__ (self, other):
		return self

	def __sub__ (self, other):
		return self

	def __rsub__ (self, other):
		return self