docs: def get_common_timestamps(source, target):
      """Return indices of timestamps from source that are also found in target.
  
      :param source: timestamps from source
      :type source: list of datetime objects
      :param target: timestamps from target
      :type target: list of datetime objects
      :return: indices of timestamps from source that are also found in target
      :rtype: list of ints
      """
      remove_from_source = set(source).difference(target)
      remove_from_source_idxs = [source.index(rm_date) for rm_date in remove_from_source]
      return [idx for idx, _ in enumerate(source) if idx not in remove_from_source_idxs]