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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 _interp(self):
 """Interpolate the cartesian coordinates. """

        if np.all(self.hrow_indices == self.row_indices):
            return self._interp1d()

        xpoints, ypoints = np.meshgrid(self.hrow_indices,
                                       self.hcol_indices)

        for num, data in enumerate(self.tie_data):
            spl = RectBivariateSpline(self.row_indices,
                                      self.col_indices,
                                      data,
                                      s=0,
                                      kx=self.kx_,
                                      ky=self.ky_)

            new_data_ = spl.ev(xpoints.ravel(), ypoints.ravel())
            self.new_data[num] = new_data_.reshape(xpoints.shape).T.copy(order='C')