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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 file_download_ui(pid, record, _record_file_factory=None, **kwargs):
 """File download view for a given record. Plug this method into your ``RECORDS_UI_ENDPOINTS`` configuration: .. code-block:: python RECORDS_UI_ENDPOINTS = dict( recid=dict( route='/records/<pid_value/files/<filename>', view_imp='invenio_records_files.utils:file_download_ui', record_class='invenio_records_files.api:Record', ) ) If ``download`` is passed as a querystring argument, the file is sent as an attachment. :param pid: The :class:`invenio_pidstore.models.PersistentIdentifier` instance. :param record: The record metadata. """

    _record_file_factory = _record_file_factory or record_file_factory
    # Extract file from record.
    fileobj = _record_file_factory(
        pid, record, kwargs.get('filename')
    )

    if not fileobj:
        abort(404)

    obj = fileobj.obj

    # Check permissions
    ObjectResource.check_object_permission(obj)

    # Send file.
    return ObjectResource.send_object(
        obj.bucket, obj,
        expected_chksum=fileobj.get('checksum'),
        logger_data={
            'bucket_id': obj.bucket_id,
            'pid_type': pid.pid_type,
            'pid_value': pid.pid_value,
        },
        as_attachment=('download' in request.args)
    )