How to use the distlib.metadata.Metadata function in distlib

def _get_distribution(self, version):
        # Source url for the package
        source_url = version['urls'][0]  # TODO: prefer whl files

        # Build the metadata
        mdata = metadata.Metadata(scheme=self.scheme)
        mdata.name = version['name']
        mdata.version = version['version']
        mdata.source_url = mdata.download_url = source_url['url']

        # Building the dist and associating the download url
        distribution = database.Distribution(mdata)
        distribution.locator = self
        return distribution

# type: (str) -> Optional[distlib.metadata.Metadata]
    parsed_metadata = None
    data = io.BytesIO()
    with vistir.contextmanagers.open_file(whl_file) as fp:
        for chunk in iter(lambda: fp.read(8096), b""):
            data.write(chunk)
    with zipfile.ZipFile(data, mode="r", compression=zipfile.ZIP_DEFLATED) as zf:
        metadata = None
        for fn in zf.namelist():
            if os.path.basename(fn) == "METADATA":
                metadata = fn
                break
        if metadata is None:
            raise RuntimeError("No metadata found in wheel: {0}".format(whl_file))
        with zf.open(metadata, "r") as metadata_fh:
            parsed_metadata = distlib.metadata.Metadata(fileobj=metadata_fh)
    return parsed_metadata

def _get_distribution(self, version):
        # Source url for the package
        source_url = version['urls'][0]  # TODO: prefer whl files

        # Build the metadata
        mdata = metadata.Metadata(scheme=self.scheme)
        mdata.name = version['name']
        mdata.version = version['version']
        mdata.download_url = source_url['url']

        # Building the dist and associating the download url
        distribution = database.Distribution(mdata)
        distribution.locator = self
        return distribution

try:

        with tempfile.TemporaryDirectory(prefix='ap_dist') as tmp_dir,\
             StringIO() as pkg_info:

            with patch('sys.stdout', new_callable=StringIO) as mock_stdout:
                dist = run_setup(script_name, ['sdist', '-d', tmp_dir,
                                               'bdist_wheel', '-d', tmp_dir])

            local_locator = DirectoryLocator(tmp_dir)
            filenames = [Path(urlparse(uri).path)
                         for uri in local_locator.get_project(dist.metadata.name)['digests'].keys()]

            dist.metadata.write_pkg_file(pkg_info)
            pkg_info.seek(0)
            metadata = Metadata(fileobj=pkg_info)
            yield metadata, filenames
    finally:
        if dist_dir:
            os.chdir(current_wd)

def get_local_wheel_metadata(wheel_file):
    # type: (str) -> Optional[distlib.metadata.Metadata]
    parsed_metadata = None
    with io.open(wheel_file, "rb") as fh:
        with zipfile.ZipFile(fh, mode="r", compression=zipfile.ZIP_DEFLATED) as zf:
            metadata = None
            for fn in zf.namelist():
                if os.path.basename(fn) == "METADATA":
                    metadata = fn
                    break
            if metadata is None:
                raise RuntimeError("No metadata found in wheel: {0}".format(wheel_file))
            with zf.open(metadata, "r") as metadata_fh:
                parsed_metadata = distlib.metadata.Metadata(fileobj=metadata_fh)
    return parsed_metadata