>>>app = Metashape.app>>>doc1 = app.document>>> type(doc1)<class 'NoneType'>>>> doc2 = Metashape.Document()>>> type(doc2)<class 'Metashape.Metashape.Document'>>>>app.document = doc2AttributeError: attribute 'document' of 'Metashape.Metashape.Application' objects is not writable