docs: def percentile(self, percentile):
          """Get a percentile of all floats in the map. Since the sorting is
          done in-place, the map is no longer safe to use after calling this
          or median()"""
          percentile = float(percentile)
          if percentile != percentile or percentile < 0 or percentile > 100:
              raise ValueError('Expected a 0 <= percentile <= 100')
          result = c_float()
          if not Gauged.map_percentile(self.ptr, percentile, byref(result)):
              raise MemoryError
          return result.value