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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 estimate_flux(self):
 """ Estimate the star's flux by summing values in the input cutout array. Missing data is filled in by interpolation to better estimate the total flux. """


        from .epsf import _interpolate_missing_data

        if np.any(self.mask):
            data_interp = _interpolate_missing_data(self.data, method='cubic',
                                                    mask=self.mask)
            data_interp = _interpolate_missing_data(data_interp,
                                                    method='nearest',
                                                    mask=self.mask)
            flux = np.sum(data_interp, dtype=np.float64)

        else:
            flux = np.sum(self.data, dtype=np.float64)

        return flux