Customize Timestampedgeojson legend

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I have not see a way to customize the API somehow to be able to add a custom label or container that can hold a part of the date(e.g. Year) as the time-lapse is playing. The year will update from 2017 to 2018 as the visualization is playing.

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Being able to extract the year into its own container on the final time-lapse visualization.

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I did some research into the API and did not see a solution. I am not sure if there is an underlying solution using JavaScript from python.

Additional context

Implementation
folium is maintained by volunteers. Can you help make a PR if we want to implement this feature?

この issue にはファイル、テスト、エントリーポイントが記載されていません。まず TimestampedGeoJson の実装と、そこから生成される JavaScript を見つけ、次に time-lapse の日付がどのように可視化に公開されているかを確認してください。ユーザーが変化する年を別のカスタム凡例コンテナに配置できれば完了です。