When generating a pre-signed URL for download and specifying response-content-disposition to set a target filename, the actual download does not contain the Content-Disposition header therefore the download file does not have the requested filename.

I have confirmed that this works corrected in S3 itself.

I'd be happy to explore a fix if anyone can point me in the right direction/location.
keys = keys if isinstance(keys, list) else [keys]
        objects = [{'Key': k} for k in keys]
        self.s3_client.delete_objects(Bucket=bucket_name, Delete={'Objects': objects})
        self.s3_client.delete_bucket(Bucket=bucket_name)
    def _perform_multipart_upload(self, bucket, key, data=None, zip=False, acl=None):
        acl = acl or 'private'
        multipart_upload_dict = self.s3_client.create_multipart_upload(Bucket=bucket, Key=key, ACL=acl)
        uploadId = multipart_upload_dict['UploadId']
        
        data = data or (5 * short_uid())
        data = to_bytes(data)
        upload_file_object = BytesIO(data)
        if zip:
            upload_file_object = BytesIO()
            with gzip.GzipFile(fileobj=upload_file_object, mode='w') as filestream:
                filestream.write(data)
        response = self.s3_client.upload_part(Bucket=bucket, Key=key,
            Body=upload_file_object, PartNumber=1, UploadId=uploadId)
        multipart_upload_parts = [{'ETag': response['ETag'], 'PartNumber': 1}]
        return self.s3_client.complete_multipart_upload(Bucket=bucket,
            Key=key, MultipartUpload={'Parts': multipart_upload_parts}, UploadId=uploadId)