gerarQRCode.py

from qgis.core import *
from qgis.gui import *
from qgis.utils import iface

@qgsfunction(args='auto', group='IPPU-RESP-OFICIOS')
def gerarQRCode(feature, parent):
    lote = iface.activeLayer().selectedFeatures()[0]
    geom = lote.geometry()
    sourceCrs = QgsCoordinateReferenceSystem(31983)
    destCrs = QgsCoordinateReferenceSystem(4326)
    tr = QgsCoordinateTransform(sourceCrs, destCrs, QgsProject.instance())
    geom.transform(tr)
    eixo_y = geom.centroid().asPoint().y()
    eixo_x = geom.centroid().asPoint().x()
    
    url = "http://maps.google.com/maps?q=loc:{0},{1}".format(eixo_y, eixo_x)
    return "<img src='https://chart.googleapis.com/chart?chs=150x150&cht=qr&chl={0}'>".format(url)