How to use the scapy.fields.BitField function in scapy

fields_desc = [
        BitEnumField('_type', 0x07, 7, LLDPDU.TYPES),
        BitFieldLenField('_length', 4, 9),
        BitField('reserved_5_available', 0, 1),
        BitField('reserved_4_available', 0, 1),
        BitField('reserved_3_available', 0, 1),
        BitField('reserved_2_available', 0, 1),
        BitField('reserved_1_available', 0, 1),
        BitField('two_port_mac_relay_available', 0, 1),
        BitField('s_vlan_component_available', 0, 1),
        BitField('c_vlan_component_available', 0, 1),
        BitField('station_only_available', 0, 1),
        BitField('docsis_cable_device_available', 0, 1),
        BitField('telephone_available', 0, 1),
        BitField('router_available', 0, 1),
        BitField('wlan_access_point_available', 0, 1),
        BitField('mac_bridge_available', 0, 1),
        BitField('repeater_available', 0, 1),
        BitField('other_available', 0, 1),
        BitField('reserved_5_enabled', 0, 1),
        BitField('reserved_4_enabled', 0, 1),
        BitField('reserved_3_enabled', 0, 1),
        BitField('reserved_2_enabled', 0, 1),
        BitField('reserved_1_enabled', 0, 1),
        BitField('two_port_mac_relay_enabled', 0, 1),
        BitField('s_vlan_component_enabled', 0, 1),
        BitField('c_vlan_component_enabled', 0, 1),
        BitField('station_only_enabled', 0, 1),
        BitField('docsis_cable_device_enabled', 0, 1),
        BitField('telephone_enabled', 0, 1),
        BitField('router_enabled', 0, 1),
        BitField('wlan_access_point_enabled', 0, 1),

XShortEnumField("proto", 0x800, ETHER_TYPES)]


class SNAP(Packet):
    name = "SNAP"
    fields_desc = [X3BytesField("OUI", 0x000000),
                   XShortEnumField("code", 0x000, ETHER_TYPES)]


conf.neighbor.register_l3(Dot3, SNAP, l2_register_l3)


class Dot1Q(Packet):
    name = "802.1Q"
    aliastypes = [Ether]
    fields_desc = [BitField("prio", 0, 3),
                   BitField("id", 0, 1),
                   BitField("vlan", 1, 12),
                   XShortEnumField("type", 0x0000, ETHER_TYPES)]

    def answers(self, other):
        if isinstance(other, Dot1Q):
            if ((self.type == other.type) and
                    (self.vlan == other.vlan)):
                return self.payload.answers(other.payload)
        else:
            return self.payload.answers(other)
        return 0

    def default_payload_class(self, pay):
        if self.type <= 1500:
            return LLC

ECA(ByteField("snap_action", None), {AA.W}),
        ECA(ByteField("most_recent_status_snapshot", None), {AA.R}),        # TODO: N field
        ECA(ByteField("reset_action", None), {AA.W}),
    ]
    mandatory_operations = {OP.Get, OP.Set, OP.GetNext}


class AdtnVlanTaggingOperation(Packet):
    name = "VlanTaggingOperation"
    fields_desc = [
        BitField("filter_outer_priority", 0, 4),
        BitField("filter_outer_vid", 0, 13),
        BitField("filter_outer_tpid_de", 0, 3),
        BitField("pad1", 0, 12),

        BitField("filter_inner_priority", 0, 4),
        BitField("filter_inner_vid", 0, 13),
        BitField("filter_inner_tpid_de", 0, 3),
        BitField("pad2", 0, 8),
        BitField("filter_ether_type", 0, 4),

        BitField("treatment_tags_to_remove", 0, 2),
        BitField("pad3", 0, 10),
        BitField("treatment_outer_priority", 0, 4),
        BitField("treatment_outer_vid", 0, 13),
        BitField("treatment_outer_tpid_de", 0, 3),

        BitField("pad4", 0, 12),
        BitField("treatment_inner_priority", 0, 4),
        BitField("treatment_inner_vid", 0, 13),
        BitField("treatment_inner_tpid_de", 0, 3),
    ]

GEN_FLAG_SUBSTITUTED_TIME: 'substituted time'
    }

    SU_FLAG_NORMAL_TIME = 0
    SU_FLAG_SUMMER_TIME = 1
    SU_FLAGS = {
        SU_FLAG_NORMAL_TIME: 'normal time',
        SU_FLAG_SUMMER_TIME: 'summer time'
    }

    informantion_element_fields = [
        LEShortField('sec_milli', 0),
        BitEnumField('iv', 0, 1, IEC104_IE_CommonQualityFlags.IV_FLAGS),
        BitEnumField('gen', 0, 1, GEN_FLAGS),
        # only valid in monitor direction ToDo: special treatment needed?
        BitField('minutes', 0, 6),
        BitEnumField('su', 0, 1, SU_FLAGS),
        BitField('reserved_2', 0, 2),
        BitField('hours', 0, 5),
        BitEnumField('weekday', 0, 3, WEEK_DAY_FLAGS),
        BitField('day-of-month', 0, 5),
        BitField('reserved_3', 0, 4),
        BitField('month', 0, 4),
        BitField('reserved_4', 0, 1),
        BitField('year', 0, 7),
    ]


class IEC104_IE_CP56TIME2A_START_TIME(IEC104_IE_CP56TIME2A):
    """
    derived IE, used for ASDU that requires two CP56TIME2A timestamps for
    defining a range

class EAP_PEAP(EAP):
    """
    draft-josefsson-pppext-eap-tls-eap-05.txt - "Protected EAP Protocol (PEAP)"
    """

    name = "PEAP"
    fields_desc = [
        ByteEnumField("code", 1, eap_codes),
        ByteField("id", 0),
        FieldLenField("len", None, fmt="H", length_of="tls_data",
                      adjust=lambda p, x: x + 10 if p.L == 1 else x + 6),
        ByteEnumField("type", 25, eap_types),
        BitField("L", 0, 1),
        BitField("M", 0, 1),
        BitField("S", 0, 1),
        BitField("reserved", 0, 3),
        BitField("version", 1, 2),
        ConditionalField(IntField("tls_message_len", 0), lambda pkt: pkt.L == 1),  # noqa: E501
        XStrLenField("tls_data", "", length_from=lambda pkt: 0 if pkt.len is None else pkt.len - (6 + 4 * pkt.L))  # noqa: E501
    ]


class EAP_FAST(EAP):
    """
    RFC 4851 - "The Flexible Authentication via Secure Tunneling
    Extensible Authentication Protocol Method (EAP-FAST)"
    """

    name = "EAP-FAST"
    fields_desc = [
        ByteEnumField("code", 1, eap_codes),
        ByteField("id", 0),

BitField("R3INFO_USERID", 0, 1),  # 63
        BitField("CHECKRADIO_EVENTS", 0, 1),  # 62
        BitField("R3INFO_FLAGS", 0, 1),  # 61
        BitField("COMBOBOX_TABLE", 0, 1),  # 60
        BitField("ISO_LANGUAGE", 0, 1),  # 59
        BitField("INPUT_REQUIRED", 0, 1),  # 58
        BitField("COMBOBOX", 0, 1),  # 57
        BitField("TYPE_SERVER", 0, 1),  # 56

        BitField("LABEL_OWNER", 0, 1),  # 71
        BitField("EVENT_DESCRIPTION", 0, 1),  # 70
        BitField("SCROLLABLE_TABSTRIP_PAGE", 0, 1),  # 69
        BitField("CONTEXT_MENU", 0, 1),  # 68
        BitField("WIN16", 0, 1),  # 67
        BitField("NUM_FIELD", 0, 1),  # 66
        BitField("USER_TURNTIME2", 0, 1),  # 65
        BitField("R3INFO_ROLLCOUNT", 0, 1),  # 64

        BitField("NOTGUI", 0, 1),  # 79
        BitField("R3INFO_IMODEUUID", 0, 1),  # 78
        BitField("VARINFO_CONTAINER", 0, 1),  # 77
        BitField("PROPFONT_VALID", 0, 1),  # 76
        BitField("TABLE_ROW_REFERENCES_2", 0, 1),  # 75
        BitField("UNUSED_1", 0, 1),  # 74
        BitField("PROPERTY_BAG", 0, 1),  # 73
        BitField("CLICKABLE_FIELD", 0, 1),  # 72

        BitField("ENJOY_IMODEUUID", 0, 1),  # 87
        BitField("CTL_PROPCACHE", 0, 1),  # 86
        BitField("DPLOADONDEMAND", 0, 1),  # 85
        BitField("JAVA_BEANS", 0, 1),  # 84

ShortField("max_simultaneous_groups", None),
        IntField("max_multicast_bw", None),
        ShortField("mcast_operations_profile_pointer", None),
        StrFixedLenField("reserved1", None, 8)
    ]

    def to_json(self):
        return json.dumps(self.fields, separators=(',', ':'))


class AllowedPreviewGroupsRow0(Packet):
    name = "AllowedPreviewGroupsRow0"
    fields_desc = [
        BitField("set_ctrl", 0, 2),
        BitField("row_part_id", 0, 3),
        BitField("reserved0", 0, 1),
        BitField("row_key", 0, 10),

        StrFixedLenField("ipv6_pad", 0, 12),
        IPField("src_ip", None),
        ShortField("vlan_id_ani", None),
        ShortField("vlan_id_uni", None)
    ]

    def to_json(self):
        return json.dumps(self.fields, separators=(',', ':'))


class AllowedPreviewGroupsRow1(Packet):
    name = "AllowedPreviewGroupsRow1"
    fields_desc = [
        BitField("set_ctrl", 0, 2),

class Dot15d4Beacon(Packet):
    name = "802.15.4 Beacon"
    fields_desc = [
        XLEShortField("src_panid", 0x0),
        dot15d4AddressField("src_addr", None, length_of="fcf_srcaddrmode"),
        # Security field present if fcf_security == True
        ConditionalField(PacketField("aux_sec_header", Dot15d4AuxSecurityHeader(), Dot15d4AuxSecurityHeader),  # noqa: E501
                         lambda pkt:pkt.underlayer.getfieldval("fcf_security") is True),  # noqa: E501

        # Superframe spec field:
        BitField("sf_sforder", 15, 4),  # not used by ZigBee
        BitField("sf_beaconorder", 15, 4),  # not used by ZigBee
        BitEnumField("sf_assocpermit", 0, 1, [False, True]),
        BitEnumField("sf_pancoord", 0, 1, [False, True]),
        BitField("sf_reserved", 0, 1),  # not used by ZigBee
        BitEnumField("sf_battlifeextend", 0, 1, [False, True]),  # not used by ZigBee  # noqa: E501
        BitField("sf_finalcapslot", 15, 4),  # not used by ZigBee

        # GTS Fields
        #  GTS Specification (1 byte)
        BitEnumField("gts_spec_permit", 1, 1, [False, True]),  # GTS spec bit 7, true=1 iff PAN cord is accepting GTS requests  # noqa: E501
        BitField("gts_spec_reserved", 0, 4),  # GTS spec bits 3-6
        BitField("gts_spec_desccount", 0, 3),  # GTS spec bits 0-2
        #  GTS Directions (0 or 1 byte)
        ConditionalField(BitField("gts_dir_reserved", 0, 1), lambda pkt:pkt.getfieldval("gts_spec_desccount") != 0),  # noqa: E501
        ConditionalField(BitField("gts_dir_mask", 0, 7), lambda pkt:pkt.getfieldval("gts_spec_desccount") != 0),  # noqa: E501
        #  GTS List (variable size)
        # TODO add a Packet/FieldListField tied to 3bytes per count in gts_spec_desccount  # noqa: E501

        # Pending Address Fields:
        #  Pending Address Specification (1 byte)

l_pay = len(pay)
            else:
                l_pay = 0
            p = p[:1] + chb(l_pay & 0x3f) + p[2:]
        if not isinstance(self.underlayer, BTLE):
            self.add_underlayer(BTLE)
        return p


class BTLE_DATA(Packet):
    name = "BTLE data header"
    fields_desc = [
        BitField("RFU", 0, 3),  # Unused
        BitField("MD", 0, 1),
        BitField("SN", 0, 1),
        BitField("NESN", 0, 1),
        BitEnumField("LLID", 0, 2, {1: "continue", 2: "start", 3: "control"}),
        ByteField("len", None),
    ]

    def post_build(self, p, pay):
        if self.len is None:
            p = p[:-1] + chb(len(pay))
        return p + pay


class BTLE_ADV_IND(Packet):
    name = "BTLE ADV_IND"
    fields_desc = [
        BDAddrField("AdvA", None),
        PacketListField("data", None, EIR_Hdr)
    ]

# Bit 0 - 4: Reserved
        ConditionalField(BitField("reserved", 0, 5), lambda pkt: pkt.cmd_identifier == 4),  # noqa: E501

        # - Route Record Command - #
        # Relay count (1 octet)
        ConditionalField(ByteField("rr_relay_count", 0), lambda pkt: pkt.cmd_identifier == 5),  # noqa: E501
        # Relay list (variable in length)
        ConditionalField(
            FieldListField("rr_relay_list", [], XLEShortField("", 0x0000), count_from=lambda pkt:pkt.rr_relay_count),  # noqa: E501
            lambda pkt:pkt.cmd_identifier == 5),

        # - Rejoin Request Command - #
        # Capability Information (1 octet)
        ConditionalField(BitField("allocate_address", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # Allocate Address  # noqa: E501
        ConditionalField(BitField("security_capability", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # Security Capability  # noqa: E501
        ConditionalField(BitField("reserved2", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # bit 5 is reserved  # noqa: E501
        ConditionalField(BitField("reserved1", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # bit 4 is reserved  # noqa: E501
        ConditionalField(BitField("receiver_on_when_idle", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # Receiver On When Idle  # noqa: E501
        ConditionalField(BitField("power_source", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # Power Source  # noqa: E501
        ConditionalField(BitField("device_type", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # Device Type  # noqa: E501
        ConditionalField(BitField("alternate_pan_coordinator", 0, 1), lambda pkt:pkt.cmd_identifier == 6),  # Alternate PAN Coordinator  # noqa: E501

        # - Rejoin Response Command - #
        # Network address (2 octets)
        ConditionalField(XLEShortField("network_address", 0xFFFF), lambda pkt:pkt.cmd_identifier == 7),  # noqa: E501
        # Rejoin status (1 octet)
        ConditionalField(ByteField("rejoin_status", 0), lambda pkt:pkt.cmd_identifier == 7),  # noqa: E501

        # - Link Status Command - #
        # Command options (1 octet)
        ConditionalField(BitField("reserved", 0, 1), lambda pkt:pkt.cmd_identifier == 8),  # Reserved  # noqa: E501
        ConditionalField(BitField("last_frame", 0, 1), lambda pkt:pkt.cmd_identifier == 8),  # Last frame  # noqa: E501