def get_existing_thumbnail(self, thumbnail_options, high_resolution=False):
        """
        Return a ``ThumbnailFile`` containing an existing thumbnail for a set
        of thumbnail options, or ``None`` if not found.
        """
        thumbnail_options = self.get_options(thumbnail_options)
        names = [
            self.get_thumbnail_name(
                thumbnail_options, transparent=False,
                high_resolution=high_resolution)]
        transparent_name = self.get_thumbnail_name(
            thumbnail_options, transparent=True,
            high_resolution=high_resolution)
        if transparent_name not in names:
            names.append(transparent_name)

        for filename in names:
            exists = self.thumbnail_exists(filename)
            if exists:
                thumbnail_file = ThumbnailFile(
                    name=filename, storage=self.thumbnail_storage,
                    thumbnail_options=thumbnail_options)
                if settings.THUMBNAIL_CACHE_DIMENSIONS:
                    # If this wasn't local storage, exists will be a thumbnail
                    # instance so we can store the image dimensions now to save
                    # a future potential query.
                    thumbnail_file.set_image_dimensions(exists)
                return thumbnail_file
def get_existing_thumbnail ( self , thumbnail_options , high_resolution = False ) : thumbnail_options = self . get_options ( thumbnail_options ) names = [ self . get_thumbnail_name ( thumbnail_options , transparent = False , high_resolution = high_resolution ) ] transparent_name = self . get_thumbnail_name ( thumbnail_options , transparent = True , high_resolution = high_resolution ) if transparent_name not in names : names . append ( transparent_name ) for filename in names : exists = self . thumbnail_exists ( filename ) if exists : thumbnail_file = ThumbnailFile ( name = filename , storage = self . thumbnail_storage , thumbnail_options = thumbnail_options ) if settings . THUMBNAIL_CACHE_DIMENSIONS : thumbnail_file . set_image_dimensions ( exists ) return thumbnail_file
Return a ``ThumbnailFile`` containing an existing thumbnail for a set
        of thumbnail options, or ``None`` if not found.