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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 train_position(self, layers, x_scale, y_scale):
 """ Create all the required x & y panel_scales y_scales and set the ranges for each scale according to the data. Notes ----- The number of x or y scales depends on the facetting, particularly the scales parameter. e.g if `scales='free'` then each panel will have separate x and y scales, and if `scales='fixed'` then all panels will share an x scale and a y scale. """

        layout = self.layout
        if self.panel_scales_x is None and x_scale:
            result = self.facet.init_scales(layout, x_scale, None)
            self.panel_scales_x = result.x

        if self.panel_scales_y is None and y_scale:
            result = self.facet.init_scales(layout, None, y_scale)
            self.panel_scales_y = result.y

        self.facet.train_position_scales(self, layers)