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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 images(gandi, label, datacenter):
 """List available system images for virtual machines. You can also filter results using label, by example: $ gandi vm images Ubuntu --datacenter LU or $ gandi vm images 'Ubuntu 10.04' --datacenter LU """

    output_keys = ['label', 'os_arch', 'kernel_version', 'disk_id',
                   'dc', 'name']

    datacenters = gandi.datacenter.list()
    result = gandi.image.list(datacenter, label)
    for num, image in enumerate(result):
        if num:
            gandi.separator_line()
        output_image(gandi, image, datacenters, output_keys)

    # also display usable disks
    result = gandi.disk.list_create(datacenter, label)
    for disk in result:
        gandi.separator_line()
        output_image(gandi, disk, datacenters, output_keys)

    return result