This project includes many functions of PyQGIS that are usually hard to find, such as

• layer symbology
  • arrows
  • points
  • custom text per point
• heatmaps using the advanced processing plugin
• loading data from CSV
• converting CSV data
• loading data from PostGIS
• creating and loading geometry data such as LineStrings from CSV or PostGIS
• saving QGIS files
• also includes information about some of the crazy setup problems with PyQGIS...

You mostly just have to look. It isn't that big.

3.12.