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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 show(key=None, display_toolbar=True):
 """Shows the current context figure in the output area. Parameters key : hashable, optional Any variable that can be used as a key for a dictionary. display_toolbar: bool (default: True) If True, a toolbar for different mouse interaction is displayed with the figure. Raises ------ KeyError When no context figure is associated with the provided key. Examples -------- """

    if key is None:
        figure = current_figure()
    else:
        figure = _context['figure_registry'][key]
    if display_toolbar:
        if not hasattr(figure, 'pyplot'):
            figure.pyplot = Toolbar(figure=figure)
        display(VBox([figure, figure.pyplot]))
    else:
        display(figure)