in node 16, stream to multipart upload is broken

[geetee24]

in 2.5.3 under node 16.....
S3WriteStream.prototype.end = function (chunk, encoding, cb) {

    this.multiPartManager.complete().then(function () {
        self.bytesWritten = self.multiPartManager.bytesWritten;
        self.emit('finish');
        execCb(cb);
    }, function (reason) {
        self.bytesWritten = self.multiPartManager.bytesWritten;
        self.emit('error', reason);
        execCb(cb);
    });

causes crash with error message: Invalid lambda response received: Lambda returned <class 'NoneType'> instead of dict