def filter_bad_names(self, images):
good_images = []<EOL>for image in images:<EOL><INDENT>if self.is_valid_filename(image):<EOL><INDENT>good_images.append(image)<EOL><DEDENT><DEDENT>return good_images if len(good_images) > <NUM_LIT:0> else None<EOL>
\
        takes a list of image elements
        and filters out the ones with bad names