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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_main(context, credentials):
 """Set up and run tasks for this iteration. http://docs.taskcluster.net/queue/worker-interaction/ Args: context (scriptworker.context.Context):
 the scriptworker context. """

    conn = aiohttp.TCPConnector(limit=context.config['aiohttp_max_connections'])
    async with aiohttp.ClientSession(connector=conn) as session:
        context.session = session
        context.credentials = credentials
        await run_tasks(context)