// Combine the raw checksums (this is what happens in CompleteMultipartUpload)
	var checksumCombined []byte
	checksumCombined = append(checksumCombined, part1Checksum.Raw...)
	checksumCombined = append(checksumCombined, part2Checksum.Raw...)
	checksumCombined = append(checksumCombined, part3Checksum.Raw...)

	// Create the final checksum (checksum of the combined checksums)

					return oi, InvalidPart{
						PartNumber: part.PartNumber,
						ExpETag:    "<nil>",
						GotETag:    err.Error(),
					}
				}
			}
			checksumCombined = append(checksumCombined, cs.Raw...)
		}

		// All parts except the last part has to be at least 5MB.
		if (i < len(parts)-1) && !isMinAllowedPartSize(currentFI.Parts[partIdx].ActualSize) {
			return oi, PartTooSmall{