code: def remove(self, value):
  		
  		try:
  			index = self._dict[value]
  		except KeyError:
  			raise ValueError('Value "%s" is not present.')
  		else:
  			del self[index]
docs: Remove value from self.
  
  		Args:
  			value: Element to remove from self
  		Raises:
  			ValueError: if element is already present