docs: def get(self, CachableItem):
          """Returns current ICachedItem for ICachableItem or None if not cached"""
          cached_item = self.mapper.get(CachableItem)
          r = self.request('get',
              self.url+"storage/collections/data/"+self.collname+'/'+cached_item.getId(),
              data={'output_mode': 'json'})
          if r.ok:
              # we need to update the object with the values found in the cache area
              data = r.json()
              for name in self.mapper.mapper:
                  setattr(cached_item, name, data[name])
              return cached_item
          return None