case c < '0' || c > '9':
			return time.Time{}, ErrHeader
		case i < len(nanoDigits):
			nanoDigits[i] = c
		}
	}
	nsecs, _ := strconv.ParseInt(string(nanoDigits[:]), 10, 64) // Must succeed after validation
	if len(ss) > 0 && ss[0] == '-' {
		return time.Unix(secs, -1*nsecs), nil // Negative correction
	}
	return time.Unix(secs, nsecs), nil
}

* Tutorial:
    * [Query Parameters and String Validations - Additional validation](https://fastapi.tiangolo.com/tutorial/query-params-str-validations/#additional-validation)
        * [Advantages of `Annotated`](https://fastapi.tiangolo.com/tutorial/query-params-str-validations/#advantages-of-annotated)

	// Order parts metadata in accordance with distribution order.
	onlineDisks, partsMetadata = shuffleDisksAndPartsMetadataByIndex(onlineDisks, partsMetadata, fi)

	// Save current erasure metadata for validation.
	currentFI := fi

	// Allocate parts similar to incoming slice.
	fi.Parts = make([]ObjectPartInfo, len(parts))

	var checksum hash.Checksum
	checksum.Type = checksumType

          <!--
            GWT issues some scary warnings while running tests, but I believe they are harmless.
            Let's take the warnings for one module, c.g.c.base.testModule, as an example:

              [INFO] Validating units:
              [INFO]    Ignored 53 units with compilation errors in first pass.
              [INFO] Compile with -strict or with -logLevel set to TRACE or DEBUG to see all errors.

	PartNumber          int                 // only useful in case of GetObject/HeadObject
	CheckPrecondFn      CheckPreconditionFn // only set during GetObject/HeadObject/CopyObjectPart preconditional valuation
	EvalMetadataFn      EvalMetadataFn      // only set for retention settings, meant to be used only when updating metadata in-place.