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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def upload_sequence_fileobj(file_obj, file_name, fields, retry_fields, session, samples_resource):
 """Uploads a single file-like object to the One Codex server via either fastx-proxy or directly to S3. Parameters file_obj : `FASTXInterleave`, `FilePassthru`, or a file-like object A wrapper around a pair of fastx files (`FASTXInterleave`) or a single fastx file. In the case of paired files, they will be interleaved and uploaded uncompressed. In the case of a single file, it will simply be passed through (`FilePassthru`) to One Codex, compressed or otherwise. If a file-like object is given, its mime-type will be sent as 'text/plain'. file_name : `string` The file_name you wish to associate this fastx file with at One Codex. fields : `dict` Additional data fields to include as JSON in the POST. Must include 'sample_id' and 'upload_url' at a minimum. retry_fields : `dict` Metadata sent to `init_multipart_upload` in the case that the upload via fastx-proxy fails. session : `requests.Session` Connection to One Codex API. samples_resource : `onecodex.models.Samples` Wrapped potion-client object exposing `init_upload` and `confirm_upload` routes to mainline. Raises ------ UploadException In the case of a fatal exception during an upload. Returns ------- `string` containing sample ID of newly uploaded file. """


    # First attempt to upload via our validating proxy
    try:
        _direct_upload(file_obj, file_name, fields, session, samples_resource)
        sample_id = fields["sample_id"]
    except RetryableUploadException:
        # upload failed--retry direct upload to S3 intermediate
        logging.error("{}: Connectivity issue, trying direct upload...".format(file_name))
        file_obj.seek(0)  # reset file_obj back to start

        try:
            retry_fields = samples_resource.init_multipart_upload(retry_fields)
        except requests.exceptions.HTTPError as e:
            raise_api_error(e.response, state="init")
        except requests.exceptions.ConnectionError:
            raise_connectivity_error(file_name)

        s3_upload = _s3_intermediate_upload(
            file_obj,
            file_name,
            retry_fields,
            session,
            samples_resource._client._root_url + retry_fields["callback_url"],  # full callback url
        )
        sample_id = s3_upload.get("sample_id", "<UUID not yet assigned>")

    logging.info("{}: finished as sample {}".format(file_name, sample_id))
    return sample_id