code: def getInfoMutator(self):
          
          if self._infoMutator:
              return self._infoMutator
          infoItems = []
          for sourceDescriptor in self.sources:
              if sourceDescriptor.layerName is not None:
                  continue
              loc = Location(sourceDescriptor.location)
              sourceFont = self.fonts[sourceDescriptor.name]
              if sourceFont is None:
                  continue
              if hasattr(sourceFont.info, "toMathInfo"):
                  infoItems.append((loc, sourceFont.info.toMathInfo()))
              else:
                  infoItems.append((loc, self.mathInfoClass(sourceFont.info)))
          bias, self._infoMutator = self.getVariationModel(infoItems, axes=self.serializedAxes, bias=self.newDefaultLocation())
          return self._infoMutator
docs: Returns a info mutator