The visualiastion will be shown on https://kanesec.github.io/vega_lite/
https://kanesec.github.io/vega_lite/2021/1.%20Intro%20to%20vega-lite/1.%20basic%20bar%20chart/
https://kanesec.github.io/vega_lite/2021/1.%20Intro%20to%20vega-lite/2.%20dupliacte%20the%20european%20city%20example/
https://kanesec.github.io/vega_lite/2021/1.%20Intro%20to%20vega-lite/3.%20stacked%20bar%20chart%20(covid)/
https://kanesec.github.io/vega_lite/2_symbol_map/
https://kanesec.github.io/vega_lite/3_choropleth_map/
https://kanesec.github.io/vega_lite/4_interactive_scatter_plot/
https://kanesec.github.io/vega_lite/5_multiple_charts_html
https://kanesec.github.io/vega_lite/6_advanced_examples