How to use the pygubu.stockimage.StockImage function in pygubu

# sbhelper widget
        sbhelper = ScrollbarHelper(self.widgetlist, scrolltype='both')

        # widgetlisttv widget
        widgetlisttv = ttk.Treeview(sbhelper)
        widgetlisttv.configure(selectmode='browse', show='tree')
        widgetlisttv.grid(column='0', row='0', sticky='nsew')
        
        sbhelper.add_child(widgetlisttv)
        sbhelper.configure(usemousewheel='true')
        sbhelper.grid(column='0', row='0', sticky='nsew')
        
        #Default widget image:
        default_image = ''
        try:
            default_image = StockImage.get('22x22-tk.default')
        except StockImageException as e:
            pass

        #Start building widget tree selector
        roots = {}
        sections = {}
        for key, wc in treelist:
            root, section = key.split('>')
            #insert root
            if root not in roots:
                roots[root] = widgetlisttv.insert('', 'end', text=root)
            #insert section
            if key not in sections:
                sections[key] = widgetlisttv.insert(roots[root], 'end', text=section)
            #insert widget
            w_image = default_image

#fix row position when using copy and paste
            #If collision, increase by 1
            row_count = self.get_max_row(root)
            if row_count > int(row) and int(col) == 0:
                row = str(row_count + 1)
                data.set_layout_property('row', row)

        image = ''
        try:
            image = StockImage.get('16x16-tk.default')
        except StockImageException as e:
            pass

        try:
            image = StockImage.get('16x16-{0}'.format(data.get_class()))
        except StockImageException as e:
            pass

        values = (data.get_class(), row, col)
        item = tree.insert(root, 'end', text=treelabel, values=values,
                image=image)
        data.attach(self)
        self.app.set_changed()

        return item

treelabel = data.get_id()
        row = col = ''
        if root != '' and 'layout' in data:
            row = data.get_layout_property('row')
            col = data.get_layout_property('column')

            # fix row position when using copy and paste
            # If collision, increase by 1
            row_count = self.get_max_row(root)
            if not from_file and (row_count > int(row) and int(col) == 0):
                row = str(row_count + 1)
                data.set_layout_property('row', row)

        image = ''
        try:
            image = StockImage.get('16x16-tk.default')
        except StockImageException:
            # TODO: notify something here
            pass

        try:
            image = StockImage.get('16x16-{0}'.format(data.get_class()))
        except StockImageException:
            # TODO: notify something here
            pass

        values = (data.get_class(), row, col)
        item = tree.insert(root, 'end', text=treelabel, values=values,
                           image=image)
        data.attach(self)
        self.treedata[item] = data

def _create_indicators(self):
        # selected indicators
        self.indicators = []
        anchors = {'nw': tk.SE, 'ne': tk.SW, 'sw': tk.NE, 'se': tk.NW}
        for sufix in self.indicators_tag:
            label = tk.Label(self.canvas,
                             image=StockImage.get('indicator_' + sufix))
            self.indicators.append(label)
            self.canvas.create_window(-10, -10, anchor=anchors[sufix],
                                      window=label, tags=sufix)

self._bold = w = CheckbuttonPropertyEditor(container1)
        img = StockImage.get('format-text-bold')
        w.parameters(style='Toolbutton', text='B', image=img,
                     onvalue='bold', offvalue='')
        w.grid(row=0, column=3, sticky='we')
        w.bind('<>', self._on_variable_changed)

        self._italic = w = CheckbuttonPropertyEditor(container1)
        img = StockImage.get('format-text-italic')
        w.parameters(style='Toolbutton', text='I', image=img,
                     onvalue='italic', offvalue='')
        w.grid(row=0, column=4, sticky='we')
        w.bind('<>', self._on_variable_changed)

        self._underline = w = CheckbuttonPropertyEditor(container1)
        img = StockImage.get('format-text-underline')
        w.parameters(style='Toolbutton', text='U', image=img,
                     onvalue='underline', offvalue='')
        w.grid(row=0, column=5, sticky='we')
        w.bind('<>', self._on_variable_changed)

        self._overstrike = w = CheckbuttonPropertyEditor(container1)
        img = StockImage.get('format-text-strikethrough')
        w.parameters(style='Toolbutton', text='S', image=img,
                     onvalue='overstrike', offvalue='')
        w.grid(row=0, column=6, sticky='we')
        w.bind('<>', self._on_variable_changed)

        self.columnconfigure(0, weight=1)
        self._populate_options()

treelabel = data.get_id()
        row = col = ''
        if root != '' and 'layout' in data:
            row = data.get_layout_property('row')
            col = data.get_layout_property('column')

            #fix row position when using copy and paste
            #If collision, increase by 1
            row_count = self.get_max_row(root)
            if row_count > int(row) and int(col) == 0:
                row = str(row_count + 1)
                data.set_layout_property('row', row)

        image = ''
        try:
            image = StockImage.get('16x16-tk.default')
        except StockImageException as e:
            pass

        try:
            image = StockImage.get('16x16-{0}'.format(data.get_class()))
        except StockImageException as e:
            pass

        values = (data.get_class(), row, col)
        item = tree.insert(root, 'end', text=treelabel, values=values,
                image=image)
        data.attach(self)
        self.app.set_changed()

        return item

# fix row position when using copy and paste
            # If collision, increase by 1
            row_count = self.get_max_row(root)
            if not from_file and (row_count > int(row) and int(col) == 0):
                row = str(row_count + 1)
                data.set_layout_property('row', row)

        image = ''
        try:
            image = StockImage.get('16x16-tk.default')
        except StockImageException:
            # TODO: notify something here
            pass

        try:
            image = StockImage.get('16x16-{0}'.format(data.get_class()))
        except StockImageException:
            # TODO: notify something here
            pass

        values = (data.get_class(), row, col)
        item = tree.insert(root, 'end', text=treelabel, values=values,
                           image=image)
        data.attach(self)
        self.treedata[item] = data

        # Update grid r/c data
        self._update_max_grid_rc(root, from_file=True)
        self.app.set_changed()

        return item

def _setup_styles(self):
        s = ttk.Style()
        s.configure('ColorSelectorButton.Toolbutton',
                    image=StockImage.get('mglass'))
        s.configure('ImageSelectorButton.Toolbutton',
                    image=StockImage.get('mglass'))
        if sys.platform == 'linux':
            #change background of comboboxes
            color = s.lookup('TEntry', 'fieldbackground')
            s.map('TCombobox', fieldbackground=[('readonly', color)])
            s.map('TSpinbox', fieldbackground=[('readonly', color)])

def show_invalid(self, value=True):
       img = ''
       if value:
           img = StockImage.get('property_invalid')
       self._error_label.configure(image=img)