Coding header is better specified in lowercase letters (#32850)
Summary:
The Python document <https://www.python.org/dev/peps/pep-0263/> gives
all examples using lowercase letters. Although it doesn't say
straightly, the following paragraph seems to indicate that uppercase
letters aren't legitimate:
> If a source file uses both the UTF-8 BOM mark signature and a magic encoding comment, the only allowed encoding for the comment is 'utf-8'. Any other encoding will cause an error.
My Emacs also complains about the uppercase letters every time I save
the file.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/32850
Differential Revision: D19663281
Pulled By: ezyang
fbshipit-source-id: 48127d3c2fd6e22dd732a2766913735136ec2ebc
