code: def sqrt_shannon_entropy(filename):
      
      data = load_grid_data(filename, "int")
      data = agg_grid(data, mode)
      phenotypes = {}
      for r in data:
          for c in r:
              if c in phenotypes:
                  phenotypes[c] += 1
              else:
                  phenotypes[c] = 1
  
      for key in phenotypes.keys():
          phenotypes[key] = sqrt(phenotypes[key])
  
      return entropy(phenotypes)
docs: Calculates Shannon entropy based on square root of phenotype count.
      This might account for relationship between population size and
      evolvability.