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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 _check_device(self, requested_device, map_device):
 """Compare the requested device with the map device and return the map device if it differs from the requested device along with a warning. """

        type_1 = torch.device(requested_device)
        type_2 = torch.device(map_device)
        if type_1 != type_2:
            warnings.warn(
                'Setting self.device = {} since the requested device ({}) '
                'is not available.'.format(map_device, requested_device),
                DeviceWarning)
            return map_device
        # return requested_device instead of map_device even though we
        # checked for *type* equality as we might have 'cuda:0' vs. 'cuda:1'.
        return requested_device