How to use the protobuf.UVarintType function in protobuf

def get_fields(cls):
        return {
            1: ('version', p.UVarintType, 0),
            2: ('type', p.UVarintType, 0),
            3: ('nonce', p.UVarintType, 0),
            4: ('gas_price', p.UVarintType, 0),
            5: ('gas_limit', p.UVarintType, 0),
            6: ('payer', p.UnicodeType, 0),
            7: ('tx_attributes', OntologyTxAttribute, p.FLAG_REPEATED),
        }

def get_fields(cls) -> Dict:
        return {
            1: ('amount', p.UVarintType, 0),
            2: ('destination', p.UnicodeType, 0),
            3: ('destination_tag', p.UVarintType, 0),
        }

def get_fields(cls):
        return {
            1: ('signature_index', p.UVarintType, 0),
            2: ('signature', p.BytesType, 0),
            3: ('serialized_tx', p.BytesType, 0),
        }

def get_fields(cls):
        return {
            1: ('address', p.UnicodeType, 0),
            2: ('address_n', p.UVarintType, p.FLAG_REPEATED),
            3: ('amount', p.UVarintType, 0),  # required
            4: ('script_type', p.UVarintType, 0),  # required
            5: ('multisig', MultisigRedeemScriptType, 0),
            6: ('op_return_data', p.BytesType, 0),
            7: ('decred_script_version', p.UVarintType, 0),
            8: ('block_hash_bip115', p.BytesType, 0),
            9: ('block_height_bip115', p.UVarintType, 0),
        }

def get_fields(cls) -> Dict:
        return {
            1: ('source_account', p.UnicodeType, 0),
            2: ('selling_asset', StellarAssetType, 0),
            3: ('buying_asset', StellarAssetType, 0),
            4: ('amount', p.SVarintType, 0),
            5: ('price_n', p.UVarintType, 0),
            6: ('price_d', p.UVarintType, 0),
            7: ('offer_id', p.UVarintType, 0),
        }

def get_fields(cls) -> Dict:
        return {
            1: ('payer', p.UVarintType, 0),
            2: ('receiver', p.UVarintType, 0),
            3: ('quantity', EosAsset, 0),
        }

def get_fields(cls) -> Dict:
        return {
            1: ('display_random', p.BoolType, 0),
            2: ('strength', p.UVarintType, 0),  # default=256
            3: ('passphrase_protection', p.BoolType, 0),
            4: ('pin_protection', p.BoolType, 0),
            5: ('language', p.UnicodeType, 0),  # default=en-US
            6: ('label', p.UnicodeType, 0),
            7: ('u2f_counter', p.UVarintType, 0),
            8: ('skip_backup', p.BoolType, 0),
            9: ('no_backup', p.BoolType, 0),
            10: ('backup_type', p.EnumType("BackupType", (0, 1, 2)), 0),  # default=Bip39
        }

def get_fields(cls) -> Dict:
        return {
            1: ('outputs_count', p.UVarintType, 0),  # required
            2: ('inputs_count', p.UVarintType, 0),  # required
            3: ('coin_name', p.UnicodeType, 0),  # default=Bitcoin
            4: ('version', p.UVarintType, 0),  # default=1
            5: ('lock_time', p.UVarintType, 0),  # default=0
            6: ('expiry', p.UVarintType, 0),
            7: ('overwintered', p.BoolType, 0),
            8: ('version_group_id', p.UVarintType, 0),
            9: ('timestamp', p.UVarintType, 0),
            10: ('branch_id', p.UVarintType, 0),
        }

def get_fields(cls) -> Dict:
        return {
            1: ('account', p.UVarintType, 0),
            2: ('code', p.UVarintType, 0),
            3: ('type', p.UVarintType, 0),
            4: ('requirement', p.UVarintType, 0),
        }

def get_fields(cls):
        return {
            1: ('address_n', p.UVarintType, p.FLAG_REPEATED),
            2: ('data', p.BytesType, 0),
            3: ('global_commitment', p.BytesType, 0),
            4: ('global_pubkey', p.BytesType, 0),
        }