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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 _create_body(self, name, size=None, volume_type=None, description=None, metadata=None, snapshot_id=None, clone_id=None, availability_zone=None, image=None):
 """ Used to create the dict required to create a new volume """

        if not isinstance(size, six.integer_types):
            raise exc.InvalidSize("Volume sizes must be integers")

        if volume_type is None:
            volume_type = "SATA"
        if description is None:
            description = ""
        if metadata is None:
            metadata = {}
        if image is not None:
            image = utils.get_id(image)
        body = {"volume": {
                "size": size,
                "snapshot_id": snapshot_id,
                "source_volid": clone_id,
                "display_name": name,
                "display_description": description,
                "volume_type": volume_type,
                "metadata": metadata,
                "availability_zone": availability_zone,
                "imageRef": image,
                }}
        return body