How to return value of text sensor in lambda?

I have a text sensor that gets its value from home assistant, and another that should return a value to print on the display. There is a problem with the second sensor. Here is the code:

display:
    platform: tm1638
    id: tm1638_display
    stb_pin: D3
    clk_pin: D2
    dio_pin: D1
    intensity: 4
    update_interval: 1s
    lambda: |-
      it.print (id(print_status).state.c_str());

text_sensor:
    - platform: homeassistant
      entity_id: "alarm_control_panel.alarmo"
      id: alarm_status

    - platform: template
      id: print_status
      lambda: |-
        if (id(alarm_status).state == "disarmed") {
          return "DISARMED";
        } else {
          return "ARMED";
        }
      update_interval: 1s

The lambda tests alarm_status, but gives these errors on the return values:

/config/esphome/alarmokeypad.yaml: In lambda function:
/config/esphome/alarmokeypad.yaml:36:16: error: could not convert '"DISARMED"' from 'const char [9]' to 'esphome::optional<std::__cxx11::basic_string<char> >'
   36 |           return "DISARMED";
      |                ^~~~~~~~~~
      |                |
      |                const char [9]
/config/esphome/alarmokeypad.yaml:38:16: error: could not convert '"ARMED"' from 'const char [6]' to 'esphome::optional<std::__cxx11::basic_string<char> >'
   38 |           return "ARMED";
      |                ^~~~~~~
      |                |
      |                const char [6]
*** [/data/alarmokeypad/.pioenvs/alarmokeypad/src/main.cpp.o] Error 1

How can I modify the return statements so that the display will print those values? Thanks for guidance.

Found my error. Should be:

        if (id(alarm_status).state == "disarmed") {
          return id(print_status).state = "DISARMED";
        }