__init__.py

# custom_components/boiler/__init__.py

configuration.yaml

sensor:
- platform: boiler
- platform: template
  sensors:
    title:
      value_template: "{{ state_attr('sensor.boiler', 'title') }}"

sensor.py

# custom_components/boiler/sensor.py
import logging
import re

import requests
from homeassistant.helpers.entity import Entity

_LOGGER = logging.getLogger(__name__)


def setup_platform(hass, config, add_entities, discovery_info=None):
    add_entities([BoilerSensor()])


class BoilerSensor(Entity):
    def __init__(self):
        self._state = None
        self._attr = None

    @property
    def entity_id(self):
        return 'sensor.boiler'

    @property
    def state(self):
        return self._state

    @property
    def state_attributes(self):
        return self._attr

    def update(self):
        _LOGGER.info("Update")
        
        r = requests.get("https://www.google.com/")
        m = re.search(r'<title>(.+?)</title>', r.text)
        self._state = m[1]
        self._attr = {
            'title': m[1]
        }