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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 delete_subscriptions(self):
 """Remove all subscriptions. Warning: This could be slow for large numbers of connected devices. If possible, explicitly delete subscriptions known to have been created. :returns: None """

        warnings.warn('This could be slow for large numbers of connected devices.'
                      'If possible, explicitly delete subscriptions known to have been created.')
        for device in self.list_connected_devices():
            try:
                self.delete_device_subscriptions(device_id=device.id)
            except CloudApiException as e:
                LOG.warning('failed to remove subscription for %s: %s', device.id, e)
                continue