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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 init(app, loop):
 """Sends a message to the webhook channel when server starts."""

    app.session = aiohttp.ClientSession(loop=loop)  # to make web requests
    app.webhook = Webhook.Async(webhook_url, session=app.session)

    em = Embed(color=0x2ecc71)
    em.set_author('[INFO] Starting Worker')
    em.description = 'Host: {}'.format(socket.gethostname())

    await app.webhook.send(embed=em)