add missing import

[tlambert03]

List of Changes

• add missing import re to utils/module_ops.py

Motivation

Selecting from multiple scene classes in a single file fails when providing a comma-separated list due to missing re import

❯ manim project/scene.py -pl
[10/07/20 15:46:14] WARNING  Option -l is deprecated please use the --quality/-q flag.
config_utils.py:660
1: SquareToCircle
2: SquareToCircle2
3: SquareToCircle3

Choose number corresponding to desired scene/arguments.
(Use comma separated list for multiple entries)
Choice(s):  1,2
Traceback (most recent call last):
  File "~/miniconda3/envs/manim/bin/manim", line 5, in <module>
    main()
  File "manim/manim/__main__.py", line 74, in main
    scene_classes_to_render = get_scenes_to_render(all_scene_classes)
  File "manim/manim/utils/module_ops.py", line 82, in get_scenes_to_render
    else prompt_user_for_choice(scene_classes)
  File "manim/manim/utils/module_ops.py", line 99, in prompt_user_for_choice
    for num_str in re.split(r"\s*,\s*", user_input.strip())
NameError: name 're' is not defined

Explanation for Changes

imports the missing library

Acknowledgement

• I have read the Contributing Guidelines

[leotrs]

@tlambert03 thanks for catching that!

@naveen521kk can you make sense of the error given by the black check? Sounds like the GH action is being flaky.

@huguesdevimeux is this something that we could easily add a test for?

[huguesdevimeux]

Completly, this is typically something that need to be tested.
Could you read the wiki to see how to do ? You basically have to write a video test in test_scene_rendering/, following the instructions on the wiki.

[leotrs]

@tlambert03 sorry for dropping the ball here!

The current master has fixed this. I have added the missing test to #193