How to use the @0x/contract-wrappers.ERC20TokenEvents.Approval function in @0x/contract-wrappers

this._callbackIfExists(err);
            }
            return;
        }
        const maybeDecodedLog = this._collisionResistantAbiDecoder.tryToDecodeLogOrNoop(
            // At this moment we are sure that no error occured and log is defined.
            logIfExists as LogEntryEvent,
        );
        const isLogDecoded = ((maybeDecodedLog as any) as LogWithDecodedArgs).event !== undefined;
        if (!isLogDecoded) {
            return; // noop
        }
        const decodedLog = (maybeDecodedLog as any) as LogWithDecodedArgs;
        const transactionHash = decodedLog.transactionHash;
        switch (decodedLog.event) {
            case ERC20TokenEvents.Approval:
            case ERC721TokenEvents.Approval: {
                // ERC20 and ERC721 Transfer events have the same name so we need to distinguish them by args
                if (decodedLog.args._value !== undefined) {
                    // ERC20
                    // Invalidate cache
                    const args = decodedLog.args as ERC20TokenApprovalEventArgs;
                    const tokenAssetData = assetDataUtils.encodeERC20AssetData(decodedLog.address);
                    this._deleteLazyStoreProxyAllowance(tokenAssetData, args._owner);
                    // Revalidate orders
                    const orderHashes = this._dependentOrderHashesTracker.getDependentOrderHashesByAssetDataByMaker(
                        args._owner,
                        tokenAssetData,
                    );
                    await this._emitRevalidateOrdersAsync(orderHashes, transactionHash);
                    break;
                } else {