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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 to_xarray(self):
 """ Return an xarray object from the pandas object. Returns ------- xarray.DataArray or xarray.Dataset Data in the pandas structure converted to Dataset if the object is a DataFrame, or a DataArray if the object is a Series. See Also -------- DataFrame.to_hdf : Write DataFrame to an HDF5 file. DataFrame.to_parquet : Write a DataFrame to the binary parquet format. Notes ----- See the `xarray docs <http://xarray.pydata.org/en/stable/>`__ Examples -------- name class max_speed num_legs 0 falcon bird 389.0 2 1 parrot bird 24.0 2 2 lion mammal 80.5 4 3 monkey mammal NaN 4 <xarray.Dataset> Dimensions: (index: 4) Coordinates: * index (index) int64 0 1 2 3 Data variables: name (index) object 'falcon' 'parrot' 'lion' 'monkey' class (index) object 'bird' 'bird' 'mammal' 'mammal' max_speed (index) float64 389.0 24.0 80.5 nan num_legs (index) int64 2 2 4 4 <xarray.DataArray 'max_speed' (index: 4)> array([389. , 24. , 80.5, nan]) Coordinates: * index (index) int64 0 1 2 3 speed date animal 2018-01-01 falcon 350 parrot 18 2018-01-02 falcon 361 parrot 15 <xarray.Dataset> Dimensions: (animal: 2, date: 2) Coordinates: * date (date) datetime64[ns] 2018-01-01 2018-01-02 * animal (animal) object 'falcon' 'parrot' Data variables: speed (date, animal) int64 350 18 361 15 """


        try:
            import xarray
        except ImportError:
            # Give a nice error message
            raise ImportError("the xarray library is not installed\n"
                              "you can install via conda\n"
                              "conda install xarray\n"
                              "or via pip\n"
                              "pip install xarray\n")

        if self.ndim == 1:
            return xarray.DataArray.from_series(self)
        elif self.ndim == 2:
            return xarray.Dataset.from_dataframe(self)

        # > 2 dims
        coords = [(a, self._get_axis(a)) for a in self._AXIS_ORDERS]
        return xarray.DataArray(self,
                                coords=coords,
                                )