UndefinedError to tmeplate sensor

I add sensor from Danfoss thermostat battery level:

- platform: template
  sensors:
    battery_thermostat_antresola:
      friendly_name: Thermostat Antresola
      value_template: '{{ states.climate.antresola_thermostat_heating_1_2_1.attributes.battery_level }}'
      unit_of_measurement: '%'

and in log there is that error:

17-01-08 16:38:45 homeassistant.components.sensor.template: UndefinedError: 'None' has no attribute 'attributes'

What I’m doing wrong?