How to use the asn1crypto.core.Sequence function in asn1crypto

_oid_pair = ('id', 'value')
    _oid_specs = {
        '1.2.3': core.Integer,
        '2.3.4': core.OctetString,
    }


class CopySeq(core.Sequence):
    _fields = [
        ('name', core.UTF8String),
        ('pair', Seq),
    ]


class NestSeqAny(core.Sequence):
    _fields = [
        ('id', core.ObjectIdentifier),
        ('value', core.Any),
    ]

    _oid_pair = ('id', 'value')
    _oid_specs = {
        '3.4.5': Seq,
    }


class NestSeqExplicit(core.Sequence):
    _fields = [
        ('id', core.ObjectIdentifier),
        ('value', NamedBits),
    ]

class RecipientEncryptedKeys(SequenceOf):
    _child_spec = RecipientEncryptedKey


class KeyAgreeRecipientInfo(Sequence):
    _fields = [
        ('version', CMSVersion),
        ('originator', OriginatorIdentifierOrKey, {'explicit': 0}),
        ('ukm', OctetString, {'explicit': 1, 'optional': True}),
        ('key_encryption_algorithm', KeyEncryptionAlgorithm),
        ('recipient_encrypted_keys', RecipientEncryptedKeys),
    ]


class KEKIdentifier(Sequence):
    _fields = [
        ('key_identifier', OctetString),
        ('date', GeneralizedTime, {'optional': True}),
        ('other', OtherKeyAttribute, {'optional': True}),
    ]


class KEKRecipientInfo(Sequence):
    _fields = [
        ('version', CMSVersion),
        ('kekid', KEKIdentifier),
        ('key_encryption_algorithm', KeyEncryptionAlgorithm),
        ('encrypted_key', OctetString),
    ]

raise ValueError(unwrap(
            '''
            Hash algorithm not known for %s
            ''',
            algorithm
        ))


class Pbkdf2Salt(Choice):
    _alternatives = [
        ('specified', OctetString),
        ('other_source', AlgorithmIdentifier),
    ]


class Pbkdf2Params(Sequence):
    _fields = [
        ('salt', Pbkdf2Salt),
        ('iteration_count', Integer),
        ('key_length', Integer, {'optional': True}),
        ('prf', HmacAlgorithm, {'default': {'algorithm': 'sha1'}}),
    ]


class KdfAlgorithmId(ObjectIdentifier):
    _map = {
        '1.2.840.113549.1.5.12': 'pbkdf2'
    }


class KdfAlgorithm(Sequence):
    _fields = [

('serial_number', Integer),
    ]


class ESSCertID(Sequence):
    _fields = [
        ('cert_hash', OctetString),
        ('issuer_serial', IssuerSerial, {'optional': True}),
    ]


class ESSCertIDs(SequenceOf):
    _child_spec = ESSCertID


class SigningCertificate(Sequence):
    _fields = [
        ('certs', ESSCertIDs),
        ('policies', CertificatePolicies, {'optional': True}),
    ]


class SetOfSigningCertificates(SetOf):
    _child_spec = SigningCertificate


class ESSCertIDv2(Sequence):
    _fields = [
        ('hash_algorithm', DigestAlgorithm, {'default': {'algorithm': 'sha256'}}),
        ('cert_hash', OctetString),
        ('issuer_serial', IssuerSerial, {'optional': True}),
    ]

class Pbmac1Params(Sequence):
    _fields = [
        ('key_derivation_func', KdfAlgorithm),
        ('message_auth_scheme', HmacAlgorithm),
    ]


class Pkcs5MacId(ObjectIdentifier):
    _map = {
        '1.2.840.113549.1.5.14': 'pbmac1',
    }


class Pkcs5MacAlgorithm(Sequence):
    _fields = [
        ('algorithm', Pkcs5MacId),
        ('parameters', Any),
    ]

    _oid_pair = ('algorithm', 'parameters')
    _oid_specs = {
        'pbmac1': Pbmac1Params,
    }

class TimeStampAndCRL(SequenceOf):
    _fields = [
        ('time_stamp', EncapsulatedContentInfo),
        ('crl', CertificateList, {'optional': True}),
    ]


class TimeStampTokenEvidence(SequenceOf):
    _child_spec = TimeStampAndCRL


class DigestAlgorithms(SequenceOf):
    _child_spec = DigestAlgorithm


class EncryptionInfo(Sequence):
    _fields = [
        ('encryption_info_type', ObjectIdentifier),
        ('encryption_info_value', Any),
    ]


class PartialHashtree(SequenceOf):
    _child_spec = OctetString


class PartialHashtrees(SequenceOf):
    _child_spec = PartialHashtree


class ArchiveTimeStamp(Sequence):
    _fields = [

}

    _reverse_map = {
        'rsa': '1.2.840.113549.1.1.1',
        'rsaes_pkcs1v15': '1.2.840.113549.1.1.1',
        'rsaes_oaep': '1.2.840.113549.1.1.7',
        'aes128_wrap': '2.16.840.1.101.3.4.1.5',
        'aes128_wrap_pad': '2.16.840.1.101.3.4.1.8',
        'aes192_wrap': '2.16.840.1.101.3.4.1.25',
        'aes192_wrap_pad': '2.16.840.1.101.3.4.1.28',
        'aes256_wrap': '2.16.840.1.101.3.4.1.45',
        'aes256_wrap_pad': '2.16.840.1.101.3.4.1.48',
    }


class KeyEncryptionAlgorithm(_ForceNullParameters, Sequence):
    _fields = [
        ('algorithm', KeyEncryptionAlgorithmId),
        ('parameters', Any, {'optional': True}),
    ]

    _oid_pair = ('algorithm', 'parameters')
    _oid_specs = {
        'rsaes_oaep': RSAESOAEPParams,
    }


class KeyTransRecipientInfo(Sequence):
    _fields = [
        ('version', CMSVersion),
        ('rid', RecipientIdentifier),
        ('key_encryption_algorithm', KeyEncryptionAlgorithm),

}


class PSourceAlgorithm(Sequence):
    _fields = [
        ('algorithm', PSourceAlgorithmId),
        ('parameters', Any, {'optional': True}),
    ]

    _oid_pair = ('algorithm', 'parameters')
    _oid_specs = {
        'p_specified': OctetString
    }


class RSAESOAEPParams(Sequence):
    _fields = [
        (
            'hash_algorithm',
            DigestAlgorithm,
            {
                'explicit': 0,
                'default': {'algorithm': 'sha1'}
            }
        ),
        (
            'mask_gen_algorithm',
            MaskGenAlgorithm,
            {
                'explicit': 1,
                'default': {
                    'algorithm': 'mgf1',

explicit = (APPLICATION,2)
	
	_fields = [
		('authenticator-vno', krb5int32, {'tag_type': TAG, 'tag': 0}),
		('crealm', Realm, {'tag_type': TAG, 'tag': 1}),
		('cname', PrincipalName, {'tag_type': TAG, 'tag': 2}),
		('cksum', Checksum, {'tag_type': TAG, 'tag': 3, 'optional': True}),
		('cusec', krb5int32, {'tag_type': TAG, 'tag': 4}),
		('ctime', KerberosTime, {'tag_type': TAG, 'tag': 5}),
		('subkey', EncryptionKey, {'tag_type': TAG, 'tag': 6, 'optional': True}),
		('seq-number', krb5uint32, {'tag_type': TAG, 'tag': 7, 'optional': True}),
		('authorization-data', AuthorizationData, {'tag_type': TAG, 'tag': 8, 'optional': True}),
	]


class PA_DATA(core.Sequence): #!!!! IT STARTS AT ONE!!!!
	_fields = [
		('padata-type', core.Integer, {'tag_type': TAG, 'tag': 1}),
		('padata-value', core.OctetString, {'tag_type': TAG, 'tag': 2}),
	]
	
class ETYPE_INFO_ENTRY(core.Sequence):
	_fields = [
		('etype', krb5int32, {'tag_type': TAG, 'tag': 0}),
		('salt', core.OctetString, {'tag_type': TAG, 'tag': 1, 'optional': True}),
		('salttype', krb5int32, {'tag_type': TAG, 'tag': 2, 'optional': True}),
	]

class ETYPE_INFO(core.SequenceOf):
	_child_spec = ETYPE_INFO_ENTRY

('crl_value', OctetString, {'explicit': 0}),
    ]


class SecretBag(Sequence):
    _fields = [
        ('secret_type_id', ObjectIdentifier),
        ('secret_value', OctetString, {'explicit': 0}),
    ]


class SafeContents(SequenceOf):
    pass


class SafeBag(Sequence):
    _fields = [
        ('bag_id', BagId),
        ('bag_value', Any, {'explicit': 0}),
        ('bag_attributes', Attributes, {'optional': True}),
    ]

    _oid_pair = ('bag_id', 'bag_value')
    _oid_specs = {
        'key_bag': PrivateKeyInfo,
        'pkcs8_shrouded_key_bag': EncryptedPrivateKeyInfo,
        'cert_bag': CertBag,
        'crl_bag': CrlBag,
        'secret_bag': SecretBag,
        'safe_contents': SafeContents
    }