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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 OnCellFontBold(self, event):
 """Cell font bold event handler"""


        with undo.group(_("Bold")):
            try:
                try:
                    weight = getattr(wx, event.weight[2:])

                except AttributeError:
                    msg = _("Weight {weight} unknown").format(
                            weight=event.weight)
                    raise ValueError(msg)

                self.grid.actions.set_attr("fontweight", weight)

            except AttributeError:
                self.grid.actions.toggle_attr("fontweight")

        self.grid.ForceRefresh()

        self.grid.update_attribute_toolbar()

        event.Skip()