TypeError: QgsVectorLayer(): argument 1 has unexpected type 'QgsVectorLayer'

Question

I'm getting this error when I try to run the following code:

a6 = processing.run("native:difference", {'INPUT':'_78b00e45_4a8e_4490_9920_f75f6e055a6a','OVERLAY':'te_afb4845c_d9b4_4498_87b0_9da89a98b2f4','OUTPUT':'TEMPORARY_OUTPUT'})
layer1 = QgsVectorLayer(a6['OUTPUT'])
QgsProject.instance().addMapLayer(layer1)

How can I solve it?

Answer 1

Try this:

a6 = processing.run("native:difference", {'INPUT':'_78b00e45_4a8e_4490_9920_f75f6e055a6a','OVERLAY':'te_afb4845c_d9b4_4498_87b0_9da89a98b2f4','OUTPUT':'TEMPORARY_OUTPUT'})
layer1 = a6['OUTPUT']
QgsProject.instance().addMapLayer(layer1)

processing.run returns a dictionary structured as {"OUTPUT": <QgsVectorLayer instance>}. a6["OUTPUT"] is already a QgsVectorLayer.