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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 _log10_Inorm_extern_planckint(self, Teff):
 """ Internal function to compute normal passband intensities using the external WD machinery that employs blackbody approximation. @Teff: effective temperature in K Returns: log10(Inorm) """


        log10_Inorm = libphoebe.wd_planckint(Teff, self.extern_wd_idx, self.wd_data["planck_table"])

        return log10_Inorm