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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 shift(self, shifts=None, fill_value=dtypes.NA, **shifts_kwargs):
 """Shift this array by an offset along one or more dimensions. Only the data is moved; coordinates stay in place. Values shifted from beyond array bounds are replaced by NaN. This is consistent with the behavior of ``shift`` in pandas. Parameters shifts : Mapping with the form of {dim: offset} Integer offset to shift along each of the given dimensions. Positive offsets shift to the right; negative offsets shift to the left. fill_value: scalar, optional Value to use for newly missing values **shifts_kwargs: The keyword arguments form of ``shifts``. One of shifts or shifts_kwarg must be provided. Returns ------- shifted : DataArray DataArray with the same coordinates and attributes but shifted data. See also -------- roll Examples -------- <xarray.DataArray (x: 3)> array([ nan, 5., 6.]) Coordinates: * x (x) int64 0 1 2 """

        variable = self.variable.shift(
            shifts=shifts, fill_value=fill_value, **shifts_kwargs)
        return self._replace(variable=variable)