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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 set_coordsys(self, coordsys):
 """ Transform coordinate system # TODO: needs expert attention """

        if coordsys in self.coordsys_mapping:
            self.coordsys = self.coordsys_mapping[coordsys]
        else:
            self.coordsys = coordsys