code: def format_value(field_info, value, section):
      
      if section == "FORMAT" and field_info.id == "FT":
          if not value:
              return "."
          elif isinstance(value, list):
              return ";".join(map(format_atomic, value))
      elif field_info.number == 1:
          if value is None:
              return "."
          else:
              return format_atomic(value)
      else:
          if not value:
              return "."
          else:
              return ",".join(map(format_atomic, value))
docs: Format possibly compound value given the FieldInfo