code: def calculate_tanimoto_set_distances(dict_of_sets: Mapping[X, Set]) -> Mapping[X, Mapping[X, float]]:
      
      result: Dict[X, Dict[X, float]] = defaultdict(dict)
  
      for x, y in itt.combinations(dict_of_sets, 2):
          result[x][y] = result[y][x] = tanimoto_set_similarity(dict_of_sets[x], dict_of_sets[y])
  
      for x in dict_of_sets:
          result[x][x] = 1.0
  
      return dict(result)
docs: Return a distance matrix keyed by the keys in the given dict.
  
      Distances are calculated based on pairwise tanimoto similarity of the sets contained.
  
      :param dict_of_sets: A dict of {x: set of y}
      :return: A similarity matrix based on the set overlap (tanimoto) score between each x as a dict of dicts