def METHOD_NAME(self):
    """
    Returns the value that will go into Xmp.variety.sourceName in image metadata.
    This will also be shown in UI.
    This could be the name of the service that is used to fetch images, e.g. Flickr.
    Default implementation is to return source_type, with uppercase first letter.
    :return: source name, e.g. "Flickr", "Unsplash", etc.
    """
    source_type = self.get_source_type()
    return source_type[0].upper() + source_type[1:]