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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def build_gui(self, container):
 """This method is called when the plugin is invoked. It builds the GUI used by the plugin into the widget layout passed as ``container``. This method could be called several times if the plugin is opened and closed. """

        vbox, sw, self.orientation = Widgets.get_oriented_box(container)
        vbox.set_border_width(4)
        vbox.set_spacing(2)

        # create the Treeview
        always_expand = self.settings.get('always_expand', True)
        color_alternate = self.settings.get('color_alternate_rows', True)
        treeview = Widgets.TreeView(auto_expand=always_expand,
                                    sortable=True,
                                    use_alt_row_color=color_alternate)
        self.treeview = treeview
        treeview.setup_table(self.columns, 3, 'MODIFIED')
        treeview.set_column_width(0, self.settings.get('ts_colwidth', 250))
        treeview.add_callback('selected', self.show_more)
        vbox.add_widget(treeview, stretch=1)

        fr = Widgets.Frame('Selected History')

        captions = (('Channel:', 'label', 'chname', 'llabel'),
                    ('Image:', 'label', 'imname', 'llabel'),
                    ('Timestamp:', 'label', 'modified', 'llabel'))
        w, b = Widgets.build_info(captions)
        self.w.update(b)

        b.chname.set_text('')
        b.chname.set_tooltip('Channel name')

        b.imname.set_text('')
        b.imname.set_tooltip('Image name')

        b.modified.set_text('')
        b.modified.set_tooltip('Timestamp (UTC)')

        captions = (('Description:-', 'llabel'), ('descrip', 'textarea'))
        w2, b = Widgets.build_info(captions)
        self.w.update(b)

        b.descrip.set_editable(False)
        b.descrip.set_wrap(True)
        b.descrip.set_text('')
        b.descrip.set_tooltip('Displays selected history entry')

        vbox2 = Widgets.VBox()
        vbox2.set_border_width(4)
        vbox2.add_widget(w)
        vbox2.add_widget(w2)

        fr.set_widget(vbox2, stretch=0)
        vbox.add_widget(fr, stretch=0)

        container.add_widget(vbox, stretch=1)

        btns = Widgets.HBox()
        btns.set_spacing(3)

        btn = Widgets.Button('Close')
        btn.add_callback('activated', lambda w: self.close())
        btns.add_widget(btn, stretch=0)
        btn = Widgets.Button("Help")
        btn.add_callback('activated', lambda w: self.help())
        btns.add_widget(btn, stretch=0)
        btns.add_widget(Widgets.Label(''), stretch=1)

        container.add_widget(btns, stretch=0)

        self.gui_up = True