code: def commit(self):
          '''
          Actually remove data returned by fetch() from the cache.
          '''
          if self._fetched is None:
              raise RuntimeError('commit() was called but nothing was fetched')
          self._cache = self._cache[self._fetched:]
          self._fetched = Nonf commit(self):
          '''
          Actually remove data returned by fetch() from the cache.
          '''
          if self._fetched is None:
              raise RuntimeError('commit() was called but nothing was fetched')
          self._cache = self._cache[self._fetched:]
          self._fetched = None
docs: Actually remove data returned by fetch() from the cache.