code: def chk_col_numbers(line_num, num_cols, tax_id_col, id_col, symbol_col):
      
  
      bad_col = ''
      if tax_id_col >= num_cols:
          bad_col = 'tax_id_col'
      elif id_col >= num_cols:
          bad_col = 'discontinued_id_col'
      elif symbol_col >= num_cols:
          bad_col = 'discontinued_symbol_col'
  
      if bad_col:
          raise Exception(
              'Input file line #%d: column number of %s is out of range' %
              (line_num, bad_col))
docs: Check that none of the input column numbers is out of range.
      (Instead of defining this function, we could depend on Python's built-in
      IndexError exception for this issue, but the IndexError exception wouldn't
      include line number information, which is helpful for users to find exactly
      which line is the culprit.)