How to use the reprounzip-qt.reprounzip_qt.gui.unpack.DockerOptions function in reprounzip-qt

record_usage(vagrant_no_chroot=True)

        if not self.magic_dirs.isChecked():
            options['args'].append('--dont-bind-magic-dirs')
            record_usage(vagrant_magic_dirs=False)

        return options


class UnpackTab(QtGui.QWidget):
    """The unpack window, that sets up a .RPZ file in a directory.
    """
    UNPACKERS = [
        ('directory', DirectoryOptions),
        ('chroot', ChrootOptions),
        ('docker', DockerOptions),
        ('vagrant', VagrantOptions),
    ]

    unpacked = QtCore.pyqtSignal(str, object)

    def __init__(self, package='', **kwargs):
        super(UnpackTab, self).__init__(**kwargs)

        layout = QtGui.QGridLayout()
        layout.addWidget(QtGui.QLabel("RPZ package:"), 0, 0)
        self.package_widget = QtGui.QLineEdit(package, enabled=False)
        layout.addWidget(self.package_widget, 0, 1)
        browse_pkg = QtGui.QPushButton("Browse")
        browse_pkg.clicked.connect(self._browse_pkg)
        layout.addWidget(browse_pkg, 0, 2)

def __init__(self):
        super(DockerOptions, self).__init__()

        self.root = QtGui.QComboBox(editable=False)
        self.root.addItems(ROOT.TEXT)
        self.add_row("Elevate privileges:", self.root)

        try:
            cmd = ['docker-machine', 'ls', '-q']
            query = subprocess.Popen(cmd, stdout=subprocess.PIPE)
            out, _ = query.communicate()
            if query.returncode != 0:
                raise subprocess.CalledProcessError(query.returncode, cmd)
            self.machine = QtGui.QComboBox(editable=False)
            if 'DOCKER_HOST' in os.environ:
                self.machine.addItem("Custom config from environment", None)
            else:
                self.machine.addItem("Default (no machine)", None)