code: func (b *BloomTrieIndexerBackend) Process(ctx context.Context, header *types.Header) error {
  	num := header.Number.Uint64() - b.section*b.size
  	if (num+1)%b.parentSize == 0 {
  		b.sectionHeads[num/b.parentSize] = header.Hash()
  	}
  	return nil
  }
docs: // Process implements core.ChainIndexerBackend