partInfo := ObjectPartInfo{
		Number:     partNumber,
		ETag:       partETag,
		Size:       partSize,
		ActualSize: actualSize,
		ModTime:    modTime,
		Index:      idx,
		Checksums:  checksums,
	}

	// Update part info if it already exists.
	for i, part := range fi.Parts {
		if partNumber == part.Number {
			fi.Parts[i] = partInfo
			return
		}
	}