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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 async def async_delete_api_key(session, host, port, api_key):
 """Delete API key from deCONZ."""

    url = 'http://{host}:{port}/api/{api_key}/config/whitelist/{api_key}'.format(
        host=host, port=str(port), api_key=api_key)

    response = await async_request(session.delete, url)

    _LOGGER.info(response)