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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 show_disk(name, call=None):
    '''
    Show the disk details of the instance

    CLI Examples:

    .. code-block:: bash

        salt-cloud -a show_disk aliyun myinstance
    '''
    if call != 'action':
        raise SaltCloudSystemExit(
            'The show_disks action must be called with -a or --action.'
        )

    ret = {}
    params = {
        'Action': 'DescribeInstanceDisks',
        'InstanceId': name
    }
    items = query(params=params)

    for disk in items['Disks']['Disk']:
        ret[disk['DiskId']] = {}
        for item in disk:
            ret[disk['DiskId']][item] = six.text_type(disk[item])

    return ret