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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 attach(self, volume_id, instance_id, device_path):
 """Attach a volume to an instance, exposing it with a device name."""

        return self.call("AttachVolume",
                         VolumeId=volume_id, InstanceId=instance_id,
                         Device=device_path)