fix a wrong type mark in a function head.

[fogsong233]

Overview: What does this pull request change?

When i am reading the source code, i notice a wrong type setting in the function, then i fix it.

Motivation and Explanation: Why and how do your changes improve the library?

Links to added or changed documentation pages

Further Information and Comments

i'm sure that there are lots of function without types, i hope it can be better.

Reviewer Checklist

• The PR title is descriptive enough for the changelog, and the PR is labeled correctly
• If applicable: newly added non-private functions and classes have a docstring including a short summary and a PARAMETERS section
• If applicable: newly added functions and classes are tested

[JasonGrace2282]

Nice catch!
Do you mind changing it from list[Mobject] into Sequence[Mobject]? That way it works with tuples as well :)

[fogsong233]

Nice catch! Do you mind changing it from list[Mobject] into Sequence[Mobject]? That way it works with tuples as well :)

ok, you are thoughtful. i have changed it : )

[JasonGrace2282]

Looks good to me, thanks :)