code: def get_bond_order(sp1, sp2, dist, tol=0.2, default_bl=None):
      
      all_lengths = obtain_all_bond_lengths(sp1, sp2, default_bl)
      # Transform bond lengths dict to list assuming bond data is successive
      # and add an imaginary bond 0 length
      lengths_list = [all_lengths[1] * (1 + tol)] + \
                     [all_lengths[idx+1] for idx in range(len(all_lengths))]
      trial_bond_order = 0
      while trial_bond_order < len(lengths_list):
          if lengths_list[trial_bond_order] < dist:
              if trial_bond_order == 0:
                  return trial_bond_order
              else:
                  low_bl = lengths_list[trial_bond_order]
                  high_bl = lengths_list[trial_bond_order - 1]
                  return trial_bond_order - (dist - low_bl) / (high_bl - low_bl)
          trial_bond_order += 1
      # Distance shorter than the shortest bond length stored,
      # check if the distance is too short
      if dist < lengths_list[-1] * (1 - tol):  # too short
          warnings.warn('%.2f angstrom distance is too short for %s and %s'
                        % (dist, sp1, sp2))
      # return the highest bond order
      return trial_bond_order - 1
docs: Calculate the bond order given the distance of 2 species
  
      Args:
          sp1 (Specie): First specie.
          sp2 (Specie): Second specie.
          dist: Their distance in angstrom
          tol (float): Relative tolerance to test. Basically, the code
              checks if the distance between the sites is larger than
              (1 + tol) * the longest bond distance or smaller than
              (1 - tol) * the shortest bond distance to determine if
              they are bonded or the distance is too short.
              Defaults to 0.2.
          default_bl: If a particular type of bond does not exist, use this
              bond length (bond order = 1). If None, a ValueError will be thrown.
  
      Returns:
          Float value of bond order. For example, for C-C bond in benzene,
          return 1.7.