gh-108113: Make it possible to create an optimized AST

[iritkatriel]

Fixes #108113.

• Issue: compile() with PyCF_ONLY_AST flag ignores the optimize arg #108113

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📚 Documentation preview 📚: https://cpython-previews--108154.org.readthedocs.build/

[carljm]

Looks like there's a docs build issue, but otherwise this LGTM.

[dreamflow]

should the new ast.PyCF_OPTIMIZED_AST
be mentioned in the compiler-flags doc ?

the compile() doc has a link to the compiler-flags doc ,
so that someone reading the compile() doc , can find out
that compile() has the ast.PyCF_OPTIMIZED_AST option .

[iritkatriel]

@dreamflow Would you like to create a PR for that doc change?

[dreamflow]

@iritkatriel yes , i'm happy to 🙂

have posted the PR #113241