When querying failed files in step 4 of Query_Import_Jobs_and_Files_Use_Case.ipynb I got error
TransportQueryError: {'message': "Page size too large, maximum page size is 25 for field 'files'", 'locations': [{'line': 5, 'column': 7}], 'path': ['fileImportJob', 'files'], 'extensions': {'code': 'BAD_REQUEST'}}
Changing line files (first: 50, status: FAILED, after: $cursor) { to files (first: 25, status: FAILED, after: $cursor) { fixes issue.