diff --git a/manimlib/scene/scene_file_writer.py b/manimlib/scene/scene_file_writer.py
index e110ad4b..4b954400 100644
--- a/manimlib/scene/scene_file_writer.py
+++ b/manimlib/scene/scene_file_writer.py
@@ -274,7 +274,7 @@ class SceneFileWriter(object):
             for pf_path in partial_movie_files:
                 if os.name == 'nt':
                     pf_path = pf_path.replace('\\', '/')
-                fp.write("file \'{}\'\n".format(pf_path))
+                fp.write(f"file \'{pf_path}\'\n")
 
         movie_file_path = self.get_movie_file_path()
         commands = [