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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 x-coordinate of a variable This method searches for the x-coordinate in the :attr:`ds`. It first checks whether there is one dimension that holds an ``'axis'`` attribute with 'X', otherwise it looks whether there is an intersection between the :attr:`x` attribute and the variables dimensions, otherwise it returns the coordinate corresponding to the last dimension of `var` Possible types var: xarray.Variable The variable to get the x-coordinate for coords: dict Coordinates to use. If None, the coordinates of the dataset in the :attr:`ds` attribute are used. Returns ------- xarray.Coordinate or None The y-coordinate or None if it could be found"""

        coords = coords or self.ds.coords
        coord = self.get_variable_by_axis(var, 'x', coords)
        if coord is not None:
            return coord
        return coords.get(self.get_xname(var))