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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 _erads2bt(self, data, channel_name):
 """Computation based on effective radiance."""

        cal_info = CALIB[self.platform_id][channel_name]
        alpha = cal_info["ALPHA"]
        beta = cal_info["BETA"]
        wavenumber = CALIB[self.platform_id][channel_name]["VC"]

        return (self._tl15(data, wavenumber) - beta) / alpha