How to use the ocrd.resolver.Resolver function in ocrd

def setUp(self):
        self.resolver = Resolver()
        self.bagger = WorkspaceBagger(self.resolver)
        self.tempdir = mkdtemp()
        self.bagdir = join(self.tempdir, 'kant_aufklaerung_1784')
        copytree(assets.path_to('kant_aufklaerung_1784'), self.bagdir)
        self.workspace_dir = join(self.bagdir, 'data')
        self.workspace = Workspace(self.resolver, directory=join(self.workspace_dir))

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

def test_validate_sequence(self):
        resolver = Resolver()
        with TemporaryDirectory() as tempdir:
            workspace = resolver.workspace_from_url(assets.path_to('kant_aufklaerung_1784/data/mets.xml'), dst_dir=tempdir)
            params_path = Path(tempdir, 'params.json')
            params_path.write_text('{"param1": true}')

            with self.assertRaisesRegex(Exception, "Input file group not contained in METS or produced by previous steps: FOO'"):
                validate_tasks([ProcessorTask.parse(x) for x in [
                    'sample-processor-required-param -I OCR-D-IMG -O OUT1 -p %s' % params_path,
                    'sample-processor-required-param -I FOO -O OUT2 -p %s' % params_path
                ]], workspace)

            with self.assertRaisesRegex(Exception, "Input fileGrp.@USE='IN'. not in METS!"):
                validate_tasks([ProcessorTask.parse(x) for x in [
                    'sample-processor-required-param -I IN -O OUT1 -p %s' % params_path,
                ]], workspace)

def setUp(self):
        if exists(BACKUPDIR):
            rmtree(BACKUPDIR)
        self.resolver = Resolver()
        self.bagger = WorkspaceBagger(self.resolver)
        self.tempdir = mkdtemp()
        self.bagdir = join(self.tempdir, 'bag')
        copytree(assets.path_to('kant_aufklaerung_1784'), self.bagdir)
        self.workspace_dir = join(self.bagdir, 'data')
        self.workspace = Workspace(self.resolver, directory=self.workspace_dir)

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

def runTest(self):
        resolver = Resolver(cache_enabled=True)
        workspace = resolver.workspace_from_url(METS_HEROLD_SMALL, directory=WORKSPACE_DIR)
        Tesseract3RegionSegmenter(workspace, inputGrp="INPUT", outputGrp="OCR-D-SEG-BLOCK").process()
        workspace.save_mets()
        Tesseract3LineSegmenter(workspace, inputGrp="OCR-D-SEG-BLOCK", outputGrp="OCR-D-SEG-LINE").process()
        workspace.save_mets()
        #  TODO takes too long
        #  Tesseract3Recognizer(workspace, inputGrp="OCR-D-SEG-LINE", outputGrp="OCR-D-OCR-TESS").process()
        workspace.save_mets()

def test_422(self):
        """
        # OCR-D/core#422
        """
        resolver = Resolver()
        with TemporaryDirectory() as tempdir:
            workspace = resolver.workspace_from_url(assets.path_to('kant_aufklaerung_1784/data/mets.xml'), dst_dir=tempdir)
            validate_tasks([ProcessorTask.parse(x) for x in [
                "sample-processor -I OCR-D-IMG       -O OCR-D-SEG-BLOCK",
                "sample-processor -I OCR-D-SEG-BLOCK -O OCR-D-SEG-LINE",
                "sample-processor -I OCR-D-SEG-LINE  -O OCR-D-SEG-WORD",
                "sample-processor -I OCR-D-SEG-WORD  -O OCR-D-OCR-TESS",
            ]], workspace)

def setUp(self):
        self.resolver = Resolver()

from flask import Flask
from flask import request

from ocrd.processor.base import run_processor
#  from ocrd.processor.segment_line.tesserocr import Tesseract3LineSegmenter
#  from ocrd.processor.segment_region.tesserocr import Tesseract3RegionSegmenter
from ocrd.resolver import Resolver

resolver = Resolver()

def create():
    app = Flask(__name__)

    #  @app.route('/processor/segment_line/tesserocr', methods=['PUT'])
    #  def _segment_line_tesserocr():
    #      run_processor(Tesseract3LineSegmenter, request.args['mets_url'], resolver)
    #      return 'DONE', 200

    #  @app.route('/processor/segment_region/tesserocr', methods=['PUT'])
    #  def _segment_region_tesserocr():
    #      run_processor(Tesseract3RegionSegmenter, request.args['mets_url'], resolver)
    #      return 'DONE', 200

    return app

def run_tasks(mets, log_level, page_id, task_strs):
    resolver = Resolver()
    workspace = resolver.workspace_from_url(mets)
    log = getLogger('ocrd.task_sequence.run_tasks')
    tasks = [ProcessorTask.parse(task_str) for task_str in task_strs]

    validate_tasks(tasks, workspace)

    # Run the tasks
    for task in tasks:

        log.info("Start processing task '%s'", task)

        # execute cli
        returncode = run_cli(
            task.executable,
            mets,
            resolver,