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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 OnMarginClick(self, evt):
 """When clicked, old and unfold as needed"""


        if evt.GetMargin() == 2:
            if evt.GetShift() and evt.GetControl():
                self.fold_all()
            else:
                line_clicked = self.LineFromPosition(evt.GetPosition())

                if self.GetFoldLevel(line_clicked) & \
                   stc.STC_FOLDLEVELHEADERFLAG:
                    if evt.GetShift():
                        self.SetFoldExpanded(line_clicked, True)
                        self.expand(line_clicked, True, True, 1)
                    elif evt.GetControl():
                        if self.GetFoldExpanded(line_clicked):
                            self.SetFoldExpanded(line_clicked, False)
                            self.expand(line_clicked, False, True, 0)
                        else:
                            self.SetFoldExpanded(line_clicked, True)
                            self.expand(line_clicked, True, True, 100)
                    else:
                        self.ToggleFold(line_clicked)