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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 _update_position(self, change):

 """ Keep position in sync with x,y,z """

        if change['type']!='update':
            return
        pt = gp_Pnt(self.x,self.y,self.z)
        if not pt.IsEqual(self.position,self.tolerance):
            self.position = pt