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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 add_mdisks(self, userid, disk_list, start_vdev=None):
 """Add disks for the userid :disks: A list dictionary to describe disk info, for example: disk: [{'size': '1g', 'format': 'ext3', 'disk_pool': 'ECKD:eckdpool1'}] """


        for idx, disk in enumerate(disk_list):
            if 'vdev' in disk:
                # this means user want to create their own device number
                vdev = disk['vdev']
            else:
                vdev = self.generate_disk_vdev(start_vdev=start_vdev,
                                               offset=idx)

            self._add_mdisk(userid, disk, vdev)
            disk['vdev'] = vdev

            if disk.get('disk_pool') is None:
                disk['disk_pool'] = CONF.zvm.disk_pool

            sizeUpper = disk.get('size').strip().upper()
            sizeUnit = sizeUpper[-1]
            if sizeUnit != 'G' and sizeUnit != 'M':
                sizeValue = sizeUpper
                disk_pool = disk.get('disk_pool')
                [diskpool_type, diskpool_name] = disk_pool.split(':')
                if (diskpool_type.upper() == 'ECKD'):
                    # Convert the cylinders to bytes
                    convert = 737280
                else:
                    # Convert the blocks to bytes
                    convert = 512
                byteSize = float(float(int(sizeValue) * convert / 1024) / 1024)
                unit = "M"
                if (byteSize > 1024):
                    byteSize = float(byteSize / 1024)
                    unit = "G"
                byteSize = "%.1f" % byteSize
                disk['size'] = byteSize + unit

        return disk_list