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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 expand(self, line, do_expand, force=False, vislevels=0, level=-1):
 """Multi-purpose expand method from original STC class"""


        lastchild = self.GetLastChild(line, level)
        line += 1

        while line <= lastchild:
            if force:
                if vislevels > 0:
                    self.ShowLines(line, line)
                else:
                    self.HideLines(line, line)
            elif do_expand:
                self.ShowLines(line, line)

            if level == -1:
                level = self.GetFoldLevel(line)

            if level & stc.STC_FOLDLEVELHEADERFLAG:
                if force:
                    self.SetFoldExpanded(line, vislevels - 1)
                    line = self.expand(line, do_expand, force, vislevels - 1)

                else:
                    expandsub = do_expand and self.GetFoldExpanded(line)
                    line = self.expand(line, expandsub, force, vislevels - 1)
            else:
                line += 1

        return line