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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 _get_instance(self):
 """ Return the instance matching the running_instance_id. """

        try:
            instance = self.compute.virtual_machines.get(
                self.running_instance_id, self.running_instance_id,
                expand='instanceView'
            )
        except Exception as error:
            raise AzureCloudException(
                'Unable to retrieve instance: {0}'.format(error)
            )

        return instance