Returns current ICachedItem for ICachableItem
        
        Args:
            CachableItem: ICachableItem, used as a reference to find a cached version
        
        Returns: ICachedItem or None, if CachableItem has not been cached

def get(self, CachableItem):
        """Returns current ICachedItem for ICachableItem
        
        Args:
            CachableItem: ICachableItem, used as a reference to find a cached version
        
        Returns: ICachedItem or None, if CachableItem has not been cached
        """
        return self.session.\
                        query(self.mapper.factory().__class__).\
                        filter(self.mapper.factory().__class__.__dict__[self.mapper.key()]==CachableItem.getId()).\
                        first()