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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 get_x(self, var, coords=None):
 """ Get the centers of the triangles in the x-dimension Parameters %(CFDecoder.get_y.parameters)s Returns ------- %(CFDecoder.get_y.returns)s"""

        if coords is None:
            coords = self.ds.coords
        # first we try the super class
        ret = super(UGridDecoder, self).get_x(var, coords)
        # but if that doesn't work because we get the variable name in the
        # dimension of `var`, we use the means of the triangles
        if ret is None or ret.name in var.dims:
            bounds = self.get_cell_node_coord(var, axis='x', coords=coords)
            if bounds is not None:
                centers = bounds.mean(axis=-1)
                x = self.get_nodes(self.get_mesh(var, coords), coords)[0]
                try:
                    cls = xr.IndexVariable
                except AttributeError:  # xarray < 0.9
                    cls = xr.Coordinate
                return cls(x.name, centers, attrs=x.attrs.copy())