Fix rebase issue from #5877

[knelli2]

Proposed changes

This was my bad. Merged #5877 too quickly.

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Code review checklist

• The code is documented and the documentation renders correctly. Run
  make doc to generate the documentation locally into BUILD_DIR/docs/html.
  Then open index.html.
• The code follows the stylistic and code quality guidelines listed in the
  code review guide.
• The PR lists upgrade instructions and is labeled bugfix or
  new feature if appropriate.

Further comments

[wthrowe]

The include is unused and misformatted. Just delete it.

[knelli2]

The commented code won't compile without it if somebody tries it. Should we just keep it, but with the proper formatting?

[wthrowe]

There shouldn't be a giant block of commented code either, but I wasn't going to ask you to fix that in this PR.

[knelli2]

@wthrowe Ok I just removed it

[wthrowe]

Filed #5926 for the commented code.