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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 _build_obs(self, **kwargs):
 """ Builds ObservationTree out of keyword arguments Ignores anything that is not a photometric bandpass. This should not be used if there are multiple stars observed. Creates self.obs """

        logging.debug('Building ObservationTree...')
        tree = ObservationTree()
        for k,v in kwargs.items():
            if k in self.ic.bands:
                if np.size(v) != 2:
                    logging.warning('{}={} ignored.'.format(k,v))
                    # continue
                    v = [v, np.nan]
                o = Observation('', k, 99) #bogus resolution=99
                s = Source(v[0], v[1])
                o.add_source(s)
                logging.debug('Adding {} ({})'.format(s,o))
                tree.add_observation(o)

        self.obs = tree