Untitled

This is the error and warning we are getting on running LabelImg.py-

labelImg.py:73: DeprecationWarning: sipPyTypeDict() is deprecated, the extension module should use sipPyTypeDictRef() instead
  class MainWindow(QMainWindow, WindowMixin):
qt.qpa.xcb: could not connect to display 
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.

If you carefully see 
1- qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
It is not able to load xcb plugin

Below is the code from 73rd line from where this class MainWindow() starts

Code-
class MainWindow(QMainWindow, WindowMixin):
    FIT_WINDOW, FIT_WIDTH, MANUAL_ZOOM = list(range(3))

    def __init__(self, default_filename=None, default_prefdef_class_file=None, default_save_dir=None):
        super(MainWindow, self).__init__()
        self.setWindowTitle(__appname__)

        # Load setting in the main thread
        self.settings = Settings()
        self.settings.load()
        settings = self.settings

        self.os_name = platform.system()

        # Load string bundle for i18n
        self.string_bundle = StringBundle.get_bundle()
        get_str = lambda str_id: self.string_bundle.get_string(str_id)

        # Save as Pascal voc xml
        self.default_save_dir = default_save_dir
        self.label_file_format = settings.get(SETTING_LABEL_FILE_FORMAT, LabelFileFormat.PASCAL_VOC)

        # For loading all image under a directory
        self.m_img_list = []
        self.dir_name = None
        self.label_hist = []
        self.last_open_dir = None
        self.cur_img_idx = 0
        self.img_count = len(self.m_img_list)

        # Whether we need to save or not.
        self.dirty = False

        self._no_selection_slot = False
        self._beginner = True
        self.screencast = "https://youtu.be/p0nR2YsCY_U"

        # Load predefined classes to the list
        self.load_predefined_classes(default_prefdef_class_file)

        if self.label_hist:
            self.default_label = self.label_hist[0]
        else:
            print("Not find:/data/predefined_classes.txt (optional)")

        # Main widgets and related state.
        self.label_dialog = LabelDialog(parent=self, list_item=self.label_hist)

        self.items_to_shapes = {}
        self.shapes_to_items = {}
        self.prev_label_text = ''

        list_layout = QVBoxLayout()
        list_layout.setContentsMargins(0, 0, 0, 0)

        # Create a widget for using default label
        self.use_default_label_checkbox = QCheckBox(get_str('useDefaultLabel'))
        self.use_default_label_checkbox.setChecked(False)
        self.default_label_combo_box = DefaultLabelComboBox(self,items=self.label_hist)

        use_default_label_qhbox_layout = QHBoxLayout()
        use_default_label_qhbox_layout.addWidget(self.use_default_label_checkbox)
        use_default_label_qhbox_layout.addWidget(self.default_label_combo_box)
        use_default_label_container = QWidget()
        use_default_label_container.setLayout(use_default_label_qhbox_layout)

        # Create a widget for edit and diffc button
        self.diffc_button = QCheckBox(get_str('useDifficult'))
        self.diffc_button.setChecked(False)
        self.diffc_button.stateChanged.connect(self.button_state)
        self.edit_button = QToolButton()
        self.edit_button.setToolButtonStyle(Qt.ToolButtonTextBesideIcon)

        # Add some of widgets to list_layout
        list_layout.addWidget(self.edit_button)
        list_layout.addWidget(self.diffc_button)
        list_layout.addWidget(use_default_label_container)

        # Create and add combobox for showing unique labels in group
        self.combo_box = ComboBox(self)
        list_layout.addWidget(self.combo_box)

        # Create and add a widget for showing current label items
        self.label_list = QListWidget()
        label_list_container = QWidget()
        label_list_container.setLayout(list_layout)
        self.label_list.itemActivated.connect(self.label_selection_changed)
        self.label_list.itemSelectionChanged.connect(self.label_selection_changed)
        self.label_list.itemDoubleClicked.connect(self.edit_label)
        # Connect to itemChanged to detect checkbox changes.
        self.label_list.itemChanged.connect(self.label_item_changed)
        list_layout.addWidget(self.label_list)



        self.dock = QDockWidget(get_str('boxLabelText'), self)
        self.dock.setObjectName(get_str('labels'))
        self.dock.setWidget(label_list_container)

        self.file_list_widget = QListWidget()
        self.file_list_widget.itemDoubleClicked.connect(self.file_item_double_clicked)
        file_list_layout = QVBoxLayout()
        file_list_layout.setContentsMargins(0, 0, 0, 0)
        file_list_layout.addWidget(self.file_list_widget)
        file_list_container = QWidget()
        file_list_container.setLayout(file_list_layout)
        self.file_dock = QDockWidget(get_str('fileList'), self)
        self.file_dock.setObjectName(get_str('files'))
        self.file_dock.setWidget(file_list_container)

        self.zoom_widget = ZoomWidget()
        self.light_widget = LightWidget(get_str('lightWidgetTitle'))
        self.color_dialog = ColorDialog(parent=self)

        self.canvas = Canvas(parent=self)
        self.canvas.zoomRequest.connect(self.zoom_request)
        self.canvas.lightRequest.connect(self.light_request)
        self.canvas.set_drawing_shape_to_square(settings.get(SETTING_DRAW_SQUARE, False))

        scroll = QScrollArea()
        scroll.setWidget(self.canvas)
        scroll.setWidgetResizable(True)
        self.scroll_bars = {
            Qt.Vertical: scroll.verticalScrollBar(),
            Qt.Horizontal: scroll.horizontalScrollBar()
        }
        self.scroll_area = scroll
        self.canvas.scrollRequest.connect(self.scroll_request)

        self.canvas.newShape.connect(self.new_shape)
        self.canvas.shapeMoved.connect(self.set_dirty)
        self.canvas.selectionChanged.connect(self.shape_selection_changed)
        self.canvas.drawingPolygon.connect(self.toggle_drawing_sensitive)

        self.setCentralWidget(scroll)
        self.addDockWidget(Qt.RightDockWidgetArea, self.dock)
        self.addDockWidget(Qt.RightDockWidgetArea, self.file_dock)
        self.file_dock.setFeatures(QDockWidget.DockWidgetFloatable)

        self.dock_features = QDockWidget.DockWidgetClosable | QDockWidget.DockWidgetFloatable
        self.dock.setFeatures(self.dock.features() ^ self.dock_features)

        # Actions
        action = partial(new_action, self)
        quit = action(get_str('quit'), self.close,
                      'Ctrl+Q', 'quit', get_str('quitApp'))

        open = action(get_str('openFile'), self.open_file,
                      'Ctrl+O', 'open', get_str('openFileDetail'))

        open_dir = action(get_str('openDir'), self.open_dir_dialog,
                          'Ctrl+u', 'open', get_str('openDir'))

        change_save_dir = action(get_str('changeSaveDir'), self.change_save_dir_dialog,
                                 'Ctrl+r', 'open', get_str('changeSavedAnnotationDir'))

        open_annotation = action(get_str('openAnnotation'), self.open_annotation_dialog,
                                 'Ctrl+Shift+O', 'open', get_str('openAnnotationDetail'))
        copy_prev_bounding = action(get_str('copyPrevBounding'), self.copy_previous_bounding_boxes, 'Ctrl+v', 'copy', get_str('copyPrevBounding'))

        open_next_image = action(get_str('nextImg'), self.open_next_image,
                                 'd', 'next', get_str('nextImgDetail'))

        open_prev_image = action(get_str('prevImg'), self.open_prev_image,
                                 'a', 'prev', get_str('prevImgDetail'))

        verify = action(get_str('verifyImg'), self.verify_image,
                        'space', 'verify', get_str('verifyImgDetail'))

        save = action(get_str('save'), self.save_file,
                      'Ctrl+S', 'save', get_str('saveDetail'), enabled=False)


Can u help fix this issue why it is not able to load plugins.