text: ## get space group symbols with certain criteria
  import os
  ref = "Space_group_ref.txt"
  
  def get_symbol_list(crystal_system):
      ''' Get short names in one crystal system
      
      argument:
      crystal_system - str - name of crystal system
      '''
      
      import linecache
      
      ind_list = []
      ref_path = os.path.join(os.path.dirname(__file__), ref) # relative path
      if os.path.isfile(ref_path):
          print('open {} as reference'.format(ref_path))
          # FIXME - temporily logic. Refine it later with loding Space_group_ref.txt
          with open(ref_path, 'r') as f:
              for ind, line in enumerate(f):
                  if crystal_system in line:
                      ind_list.append(ind-2)
                      # print(ind-2) debug line
          symb_list = []
          for ind in ind_list:
              read = linecache.getline(ref_path, ind)
              position_ind = [ ind for ind, x in enumerate(read) if x== '"']
              #print('position_ind = {}'.format(position_ind)) debug line
              if position_ind:
                  head = min(position_ind)
                  tail = max(position_ind)
                  symb = read[head+1:tail]
                  print(symb) #degug line
                  symb_list.append(symb)
              else:
                  pass
          return symb_list
  