docs: def pot_dict_from_string(pot_data):
          """
          Creates atomic symbol/potential number dictionary
          forward and reverse
  
          Arg:
              pot_data: potential data in string format
  
          Returns:
              forward and reverse atom symbol and potential number dictionaries.
          """
  
          pot_dict = {}
          pot_dict_reverse = {}
          begin = 0
          ln = -1
  
          for line in pot_data.split("\n"):
              try:
                  if begin == 0 and line.split()[0] == "0":
                      begin += 1
                      ln = 0
                  if begin == 1:
                      ln += 1
                  if ln > 0:
                      atom = line.split()[2]
                      index = int(line.split()[0])
                      pot_dict[atom] = index
                      pot_dict_reverse[index] = atom
              except (ValueError, IndexError):
                  pass
          return pot_dict, pot_dict_reverse