code: def compute_percentile(self, percentage):
          
          all_patches = self.get_all_patches()
          return all_patches[
              int(len(all_patches) * percentage / 100)
          ].start_position
docs: Returns a Position object that represents percentage%-far-of-the-way
          through the larger task, as specified by this query.
  
          @param percentage    a number between 0 and 100.