docs: def _lsm_fix_strip_offsets(self):
          """Unwrap strip offsets for LSM files greater than 4 GB.
  
          Each series and position require separate unwrapping (undocumented).
  
          """
          if self.filehandle.size < 2**32:
              return
  
          pages = self.pages
          npages = len(pages)
          series = self.series[0]
          axes = series.axes
  
          # find positions
          positions = 1
          for i in 0, 1:
              if series.axes[i] in 'PM':
                  positions *= series.shape[i]
  
          # make time axis first
          if positions > 1:
              ntimes = 0
              for i in 1, 2:
                  if axes[i] == 'T':
                      ntimes = series.shape[i]
                      break
              if ntimes:
                  div, mod = divmod(npages, 2*positions*ntimes)
                  assert mod == 0
                  shape = (positions, ntimes, div, 2)
                  indices = numpy.arange(product(shape)).reshape(shape)
                  indices = numpy.moveaxis(indices, 1, 0)
          else:
              indices = numpy.arange(npages).reshape(-1, 2)
  
          # images of reduced page might be stored first
          if pages[0]._offsetscounts[0][0] > pages[1]._offsetscounts[0][0]:
              indices = indices[..., ::-1]
  
          # unwrap offsets
          wrap = 0
          previousoffset = 0
          for i in indices.flat:
              page = pages[int(i)]
              dataoffsets = []
              for currentoffset in page._offsetscounts[0]:
                  if currentoffset < previousoffset:
                      wrap += 2**32
                  dataoffsets.append(currentoffset + wrap)
                  previousoffset = currentoffset
              page._offsetscounts = dataoffsets, page._offsetscounts[1]