add tuple keyword (#25474)
Summary:
Doesn't really add much functionality, since inputs to `tuple()` which we can statically infer the output size is pretty much just tuples. Does improve the error message though.
Fix for https://github.com/pytorch/pytorch/issues/24000
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25474
Differential Revision: D17133800
Pulled By: eellison
fbshipit-source-id: 41a052895e6ed24a384ec6f8aef0a6769ac094e6
