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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 device_locked(self, device):
 """Show lock notification for specified device object."""

        if not self._mounter.is_handleable(device):
            return
        self._show_notification(
            'device_locked',
            _('Device locked'),
            _('{0.device_presentation} locked', device),
            device.icon_name)