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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def OnCellFontSize(self, event):
 """Cell font size event handler"""


        with undo.group(_("Font size")):
            self.grid.actions.set_attr("pointsize", event.size)

        self.grid.ForceRefresh()

        self.grid.update_attribute_toolbar()

        event.Skip()