How to use the ocrd.Resolver function in ocrd

def _sample_ws_for_overwrite(self):
        resolver = Resolver()
        with TemporaryDirectory() as tempdir:
            ws = resolver.workspace_from_nothing(directory=tempdir)
            ws.add_file('IN-GRP',  pageId='pID1', ID='fID1', mimetype='image/tiff', content='CONTENT', local_filename=join(tempdir, 'ID1.tif'))
            ws.add_file('OUT-GRP', pageId='pID2', ID='fID2', mimetype='image/tiff', content='CONTENT', local_filename=join(tempdir, 'ID2.tif'))
            ws.add_file('OUT-GRP', pageId='pID3', ID='fID3', mimetype='image/tiff', content='CONTENT', local_filename=join(tempdir, 'ID3.tif'))
            ws.add_file('OUT-GRP', pageId='pID4', ID='fID4', mimetype='image/tiff', content='CONTENT', local_filename=join(tempdir, 'ID4.tif'))
            ws.save_mets()
            yield ws

def setUp(self):
        self.resolver = Resolver()
        self.ws = self.resolver.workspace_from_url(assets.url_of('SBB0000F29300010000/data/mets.xml'))

def testProcessorProfiling(self):
        log_capture_string = FIFOIO(256)
        ch = logging.StreamHandler(log_capture_string)
        ch.setFormatter(logging.Formatter(LOG_FORMAT))
        getLogger('ocrd.process.profile').setLevel('DEBUG')
        getLogger('ocrd.process.profile').addHandler(ch)

        run_processor(DummyProcessor, resolver=Resolver(), mets_url=assets.url_of('SBB0000F29300010000/data/mets.xml'))

        log_contents = log_capture_string.getvalue()
        log_capture_string.close()
        # with open('/tmp/debug.log', 'w') as f:
        #     f.write(log_contents)
        # Check whether profile information has been logged. Dummy should finish in under 0.1s
        self.assertTrue(match(r'.*Executing processor \'ocrd-test\' took 0.\d+s.*', log_contents))

def runTest(self):
        resolver = Resolver()
        workspace = resolver.workspace_from_url(METS_HEROLD_SMALL, dst_dir=WORKSPACE_DIR)
        TesserocrSegmentRegion(workspace, input_file_grp="OCR-D-IMG", output_file_grp="OCR-D-SEG-BLOCK").process()
        TesserocrSegmentLine(workspace, input_file_grp="OCR-D-SEG-BLOCK", output_file_grp="OCR-D-SEG-LINE").process()
        TesserocrSegmentWord(workspace, input_file_grp="OCR-D-SEG-LINE", output_file_grp="OCR-D-SEG-WORD").process()
        workspace.save_mets()

def setUp(self):
        self.maxDiff = None
        self.resolver = Resolver()
        initLogging()
        self.runner = CliRunner(mix_stderr=False)

def __init__(self, directory, mets_basename, automatic_backup):
        self.directory = directory
        self.resolver = Resolver()
        self.mets_basename = mets_basename
        self.automatic_backup = automatic_backup