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?

该 issue 未指定文件、测试或入口点。首先定位 TimestampedGeoJson 的实现及其生成的 JavaScript，然后确定时间推移日期是如何暴露给可视化的。完成的标准是用户可以将不断变化的年份放置在单独的自定义图例容器中。