You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: sans.go
    path of file: ./repos/podman/vendor/github.com/sigstore/sigstore/pkg/cryptoutils
    
    the code of the file until where you have to start completion: // Copyright 2022 The Sigstore Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under 
    
func UnmarshalOtherNameSAN(exts []pkix.Extension) (string, error) {
	var otherNames []string

	for _, e := range exts {
		if !e.Id.Equal(SANOID) {
			continue
		}

		var seq asn1.RawValue
		rest, err := asn1.Unmarshal(e.Value, &seq)
		if err != nil {
			return "", err
		} else if len(rest) != 0 {
			return "", fmt.Errorf("trailing data after X.509 extension")
		}
		if !seq.IsCompound || seq.Tag != asn1.TagSequence || seq.Class != asn1.ClassUniversal {
			return "", asn1.StructuralError{Msg: "bad SAN sequence"}
		}

		rest = seq.Bytes
		for len(rest) > 0 {
			var v asn1.RawValue
			rest, err = asn1.Unmarshal(rest, &v)
			if err != nil {
				return "", err
			}

			// skip all GeneralName fields except OtherName
			if v.Tag != 0 {
				continue
			}

			var other OtherName
			if _, err := asn1.UnmarshalWithParams(v.FullBytes, &other, "tag:0"); err != nil {
				return "", fmt.Errorf("could not parse requested OtherName SAN: %w", err)
			}
			if !other.ID.Equal(OIDOtherName) {
				return "", fmt.Errorf("unexpected OID for OtherName, expected %v, got %v", OIDOtherName, other.ID)
			}
			otherNames = append(otherNames, other.Value)
		}
	}

	if len(otherNames) == 0 {
		return "", errors.New("no OtherName found")
	}
	if len(otherNames) != 1 {
		return "", errors.New("expected only one OtherName")
	}

	return otherNames[0], nil
}