docs: def get_time(self, idx):
          """Time for each TIFF file
  
          If there are no metadata keyword arguments defined for the
          TIFF file format, then the zip file `date_time` value is
          used.
          """
          # first try to get the time from the TIFF file
          # (possible meta data keywords)
          ds = self._get_dataset(idx)
          thetime = ds.get_time()
          if np.isnan(thetime):
              # use zipfile date_time
              zf = zipfile.ZipFile(self.path)
              info = zf.getinfo(self.files[idx])
              timetuple = tuple(list(info.date_time) + [0, 0, 0])
              thetime = time.mktime(timetuple)
          return thetime