code: def bootstrap(self, mc_bit=0x10, seed=None):
          
          if seed is not None: np.random.seed(seed)
          data = copy.deepcopy(self.data)
          idx = np.random.randint(0,len(data),len(data))
          data[self.config['catalog']['mag_1_field']][:] = self.mag_1[idx]
          data[self.config['catalog']['mag_err_1_field']][:] = self.mag_err_1[idx]
          data[self.config['catalog']['mag_2_field']][:] = self.mag_2[idx]
          data[self.config['catalog']['mag_err_2_field']][:] = self.mag_err_2[idx]
          data[self.config['catalog']['mc_source_id_field']][:] |= mc_bit
          return Catalog(self.config, data=data)
docs: Return a random catalog by boostrapping the colors of the objects in the current catalog.