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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(block=False):
 """Show current figures using vispy Parameters block : bool If True, blocking mode will be used. If False, then non-blocking / interactive mode will be used. Returns ------- canvases : list List of the vispy canvases that were created. """

    if not has_matplotlib():
        raise ImportError('Requires matplotlib version >= 1.2')
    cs = [_mpl_to_vispy(plt.figure(ii)) for ii in plt.get_fignums()]
    if block and len(cs) > 0:
        cs[0].app.run()
    return cs