'Updates metadata elements from a given OS image reference.
image_name:
The name of the image to update.
os_image:
An instance of OSImage class.
os_image.label: Optional. Specifies an identifier for the image.
os_image.description: Optional. Specifies the description of the image.
os_image.language: Optional. Specifies the language of the image.
os_image.image_family:
Optional. Specifies a value that can be used to group VM Images.
os_image.recommended_vm_size:
Optional. Specifies the size to use for the Virtual Machine that
is created from the VM Image.
os_image.eula:
Optional. Specifies the End User License Agreement that is
associated with the image. The value for this element is a string,
but it is recommended that the value be a URL that points to a EULA.
os_image.icon_uri:
Optional. Specifies the URI to the icon that is displayed for the
image in the Management Portal.
os_image.small_icon_uri:
Optional. Specifies the URI to the small icon that is displayed for
the image in the Management Portal.
os_image.privacy_uri:
Optional. Specifies the URI that points to a document that contains
the privacy policy related to the image.
os_image.published_date:
Optional. Specifies the date when the image was added to the image
repository.
os.image.media_link:
Required: Specifies the location of the blob in Windows Azure
blob store where the media for the image is located. The blob
location must belong to a storage account in the subscription
specified by the <subscription-id> value in the operation call.
Example:
http://example.blob.core.windows.net/disks/mydisk.vhd
os_image.name:
Specifies a name for the OS image that Windows Azure uses to
identify the image when creating one or more VM Roles.
os_image.os:
The operating system type of the OS image. Possible values are:
Linux, Windows'

def update_os_image_from_image_reference(self, image_name, os_image):

    _validate_not_none('image_name', image_name)
    _validate_not_none('os_image', os_image)
    return self._perform_put(self._get_image_path(image_name), _XmlSerializer.update_os_image_to_xml(os_image), async=True)
