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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 register_bpass(self, telescope, klass):
 """Register a Bandpass class."""


        if telescope in self._bpass_classes:
            raise AlreadyDefinedError('bandpass class for %s already '
                                      'defined', telescope)
        self._note(telescope, None)
        self._bpass_classes[telescope] = klass
        return self