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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_xname(self, var, coords=None):
 """Get the name of the x-dimension This method gives the name of the x-dimension (which is not necessarily the name of the coordinate if the variable has a coordinate attribute) Parameters var: xarray.Variables The variable to get the dimension for coords: dict The coordinates to use for checking the axis attribute. If None, they are not used Returns ------- str The coordinate name See Also -------- get_x"""

        if coords is not None:
            coord = self.get_variable_by_axis(var, 'x', coords)
            if coord is not None and coord.name in var.dims:
                return coord.name
        dimlist = list(self.x.intersection(var.dims))
        if dimlist:
            if len(dimlist) > 1:
                warn("Found multiple matches for x coordinate in the variable:"
                     "%s. I use %s" % (', '.join(dimlist), dimlist[0]),
                     PsyPlotRuntimeWarning)
            return dimlist[0]
        # otherwise we return the coordinate in the last position
        return var.dims[-1]