Invalid format string errors

I’m not sure if this should go in programming or configuration categories:-
I get a lot of these errors -----

16-06-23 22:19:00 INFO (ThreadPool Worker 0) [requests.packages.urllib3.connectionpool] Starting new HTTPS connection (1): api.forecast.io
16-06-23 22:19:01 INFO (ThreadPool Worker 0) [homeassistant.core] Bus:Handling <Event state_changed[L]: entity_id=sensor.weather_temperature, new_state=<state sensor.weather_temperature=17.2; unit_of_measurement=°C, friendly_name=Weather Temperature @ 2016-06-23T22:19:01.047690+01:00>, old_state=<state sensor.weather_temperature=17.3; unit_of_measurement=°C, friendly_name=Weather Temperature @ 2016-06-23T22:13:01.278039+01:00>>
16-06-23 22:19:01 INFO (ThreadPool Worker 0) [homeassistant.core] Bus:Handling <Event state_changed[L]: entity_id=sensor.weather_apparent_temperature, new_state=<state sensor.weather_apparent_temperature=17.2; unit_of_measurement=°C, friendly_name=Weather Apparent Temperature @ 2016-06-23T22:19:01.061204+01:00>, old_state=<state sensor.weather_apparent_temperature=17.3; unit_of_measurement=°C, friendly_name=Weather Apparent Temperature @ 2016-06-23T22:13:01.292052+01:00>>
16-06-23 22:19:01 ERROR (ThreadPool Worker 3) [homeassistant.core] BusHandler:Exception doing job
Traceback (most recent call last):
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\homeassistant\core.py", line 809, in job_handler
    func(arg)
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\homeassistant\helpers\event.py", line 51, in state_change_listener
    event.data.get('new_state'))
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\homeassistant\components\automation\template.py", line 36, in state_changed_listener
    template_result = condition.template(hass, value_template)
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\homeassistant\helpers\condition.py", line 206, in template
    value = render(hass, value_template, variables)
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\homeassistant\helpers\template.py", line 61, in render
    }).render(kwargs).strip()
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\jinja2\environment.py", line 989, in render
    return self.environment.handle_exception(exc_info, True)
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\jinja2\environment.py", line 754, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\jinja2\_compat.py", line 37, in reraise
    raise value.with_traceback(tb)
  File "<template>", line 1, in top-level template code
  File "C:\Users\MyPc\AppData\Local\Programs\Python\Python35-32\lib\site-packages\jinja2\sandbox.py", line 355, in call
    return __context.call(__obj, *args, **kwargs)
ValueError: Invalid format string

I don’t think I’ve changed anything that could cause this, does anyone have any ideas?

OK, I found a template error :stuck_out_tongue: