Add elements helper

[vdegenne]

In response to my issue ticket (#272).

This is PR to show what I actually meant and because I hope this small feature gets implemented.

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[vdegenne]

I signed it!

[googlebot]

CLAs look good, thanks!

[bicknellr]

Hi, I'm setting the base branch of this PR to master so that we can delete __auto_generated_3.0_preview.