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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 on_help_menu_open(self, widget):
 """Open Help menu"""

        self.original_widget = urwid.Overlay(self.help_menu.main_window,
                                             self.original_widget,
                                             ('relative', self.left_margin),
                                             self.help_menu.get_size()[1],
                                             ('relative', self.top_margin),
                                             self.help_menu.get_size()[0])