code: def get_snapshot_by_version(obj, version=0):
      
      if version < 0:
          return None
      snapshots = get_snapshots(obj)
      if version > len(snapshots) - 1:
          return None
      return snapshots[version]
docs: Get a snapshot by version
  
      Snapshot versions begin with `0`, because this is the first index of the
      storage, which is a list.
  
      :param obj: Content object
      :param version: The index position of the snapshot in the storage
      :returns: Snapshot at the given index position