Update 07-visualization-ggplot-python.md

Closes #599

Correcte API link, setup-plotnine, and ggplot2-cheat-sheet.

Also fixed documentation link by pointing it to read me on github.  That read me directs users to plotnine homepage which has less guidance than the read me and then punts to gg-plot documentation for additional coverage.   I am open to considering better documentation options.

episodes/07-visualization-ggplot-python.md

@@ -631,12 +631,12 @@ my_plot.save("scatterplot.png", width=10, height=10, dpi=300)
 
 
 
-[plotnine]: https://plotnine.readthedocs.io/en/stable
+[plotnine]: https://github.com/has2k1/plotnine?tab=readme-ov-file
 [ggplot2]: https://ggplot2.tidyverse.org
 [grammar-of-graphics]: https://link.springer.com/book/10.1007%2F0-387-28695-0
-[setup-plotnine]: https://datacarpentry.org/python-ecology-lesson/setup.html#required-python-packages
-[plotnine-api]: https://plotnine.readthedocs.io/en/stable/api.html#color-and-fill-scales
-[ggplot2-cheat-sheet]: https://www.rstudio.com/wp-content/uploads/2015/08/ggplot2-cheatsheet.pdf
+[setup-plotnine]: https://datacarpentry.org/python-ecology-lesson/#required-python-packages
+[plotnine-api]: https://plotnine.org/reference/
+[ggplot2-cheat-sheet]: https://rstudio.github.io/cheatsheets/html/data-visualization.html
 
 
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