<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def inband_solarflux(self, rsr, scale=1.0, **options):
 """Derive the inband solar flux for a given instrument relative spectral response valid for an earth-sun distance of one AU. """

        return self._band_calculations(rsr, True, scale, **options)