text: Title: Seaborn Heatmap Documentation
  Body: Hi all I was looking at your [heatmap example](https://seaborn.pydata.org/examples/spreadsheet_heatmap.html) and found that the `pandasDataframe.pivot()` function does not work locally as called.
  
  I had to change 
  `flights = flights_long.pivot("month", "year", "passengers")` 
  to 
  `flights = flights_long.pivot(index="month", columns="year", values="passengers")`, specifying the kwargs.
  
  I'm working through this because I am making an Advanced Visualization Cookbook for [Project Pythia](https://projectpythia.org/) and trying to provide an overview of all the different plotting libraries scientific python programmers have ever asked me about during plotting tutorials. If you'd like input or feedback on how your project is summarized or if you'd like a workflow to be featured in our interactive plotting chapter please let me know.