Zooms grid rows

def _zoom_rows(self, zoom):
        """Zooms grid rows"""

        self.grid.SetDefaultRowSize(self.grid.std_row_size * zoom,
                                    resizeExistingRows=True)
        self.grid.SetRowLabelSize(self.grid.row_label_size * zoom)

        for row, tab in self.code_array.row_heights:
            if tab == self.grid.current_table and \
               row < self.grid.code_array.shape[0]:
                base_row_width = self.code_array.row_heights[(row, tab)]
                if base_row_width is None:
                    base_row_width = self.grid.GetDefaultRowSize()
                zoomed_row_size = base_row_width * zoom
                self.grid.SetRowSize(row, zoomed_row_size)