Toolsdev 389 accessibility summary

[delfanbaum]

Verified on staging:

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            9781492056355
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            Fluent Python
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            Fluent Python
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            While some O&amp;#x2019;Reilly content may include additional
            accessibility features, all of our content supports language tagging
            and structural, landmark, and index navigation. No accessibility
            features are actively disabled.
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