def METHOD_NAME(self, custom_placeholder, data, view_kwargs):
    """
    method to update image sizes before updating the custom placeholder
    :param custom_placeholder:
    :param data:
    :param view_kwargs:
    :return:
    """
    if (
        data.get('original_image_url')
        and data['original_image_url'] != custom_placeholder.original_image_url
    ):
        uploaded_images = create_save_image_sizes(
            data['original_image_url'], 'custom-placeholders', custom_placeholder.id
        )
        data['original_image_url'] = uploaded_images['original_image_url']
        data['large_image_url'] = uploaded_images['large_image_url']
        data['thumbnail_image_url'] = uploaded_images['thumbnail_image_url']
        data['icon_image_url'] = uploaded_images['icon_image_url']