code: def columnCount(self, parent=None):
          
          if self._separateFieldOrientation == Qt.Horizontal:
              return self._nCols * len(self._fieldNames)
          else:
              return self._nCols
docs: The number of columns of the sliced array.
              The 'parent' parameter can be a QModelIndex. It is ignored since the number of
              columns does not depend on the parent.