Minor error in documentation in https://pro.arcgis.com/en/pro-app/latest/arcpy/mapping/guidelines-for-arcpy-mapping.htm
An example of using the CURRENT keyword.
aprx = arcpy.mp.ArcGISProject('current')should be aprx = arcpy.mp.ArcGISProject('CURRENT')
There is a link on the bottom right of any help document page where you can notify the Help people about help content issues. If you could notify them of any issues there, they will be addressed.
To be fair, "current" works.
# this works, too aprx = arcpy.mp.ArcGISProject('CuRrEnT')
