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    The hass object

    The `HomeAssistant` instance that integrations get, with access to the state machine, the event bus, actions, and the configuration.

    In code
    HomeAssistanthass
    Also
    hass

    Almost every function in Home Assistant Core takes hass as its first argument. It is how code reaches everything else: hass.states, hass.bus, hass.services, and hass.config.

    hass is a name in code. In text, write Home Assistant.

    Related terms

    • State machineThe part of Home Assistant Core that holds the current state of every entity.
    • EventA message on the event bus that something happened, like a state change or a button press. Any code can listen to events.
    • ActionSomething Home Assistant can do, like turning on a light or sending a notification. Automations, scripts, and dashboards perform actions.
    • Event loopThe asyncio loop that runs Home Assistant Core. Code that blocks it, like waiting on the network without `await`, stops everything else.