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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 _srads2bt(self, data, channel_name):
 """Computation based on spectral radiance."""

        a__, b__, c__ = BTFIT[channel_name]
        wavenumber = CALIB[self.platform_id][channel_name]["VC"]
        temp = self._tl15(data, wavenumber)

        return a__ * temp * temp + b__ * temp + c__