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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 unblock_pin(ctx, puk, new_pin):
 """ Unblock the PIN. Reset the PIN using the PUK code. """

    controller = ctx.obj['controller']
    if not puk:
        puk = click.prompt(
            'Enter PUK', default='', show_default=False,
            hide_input=True, err=True)
    if not new_pin:
        new_pin = click.prompt(
            'Enter a new PIN', default='',
            show_default=False, hide_input=True, err=True)
    controller.unblock_pin(puk, new_pin)