Make api post request.

async def api_post(self, url, params):
        """Make api post request."""
        post = None
        try:
            with async_timeout.timeout(DEFAULT_TIMEOUT, loop=self._event_loop):
                post = await self._api_session.post(
                    url, params=params)
            if post.status != 204:
                _LOGGER.error('Error posting Emby data: %s', post.status)
                return None

            post_result = await post.text()
            return post_result

        except (aiohttp.ClientError, asyncio.TimeoutError,
                ConnectionRefusedError) as err:
            _LOGGER.error('Error posting Emby data: %s', err)
            return None