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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 get(self, telescope, band):
 """Get a Bandpass object for a known telescope and filter."""


        klass = self._bpass_classes.get(telescope)
        if klass is None:
            raise NotDefinedError('bandpass data for %s not defined', telescope)

        bp = klass()
        bp.registry = self
        bp.telescope = telescope
        bp.band = band
        return bp