code: def missing(self, *args, **kwds):
          
          from functools import reduce
  
          indexer = kwds['indexer']
          freq = kwds['freq'] or generic.default_freq(**indexer)
  
          miss = (checks.missing_any(generic.select_time(da, **indexer), freq) for da in args)
          return reduce(np.logical_or, miss)
docs: Return whether an output is considered missing or not.