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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:
 def ssh_calc_aws(node):
 """Calculate default ssh-user based on image-if of AWS instance."""

    userlu = {"ubunt": "ubuntu", "debia": "admin", "fedor": "root",
              "cento": "centos", "openb": "root"}
    image_name = node.driver.get_image(node.extra['image_id']).name
    if not image_name:
        image_name = node.name
    usertemp = ['name'] + [value for key, value in list(userlu.items())
                           if key in image_name.lower()]
    usertemp = dict(zip(usertemp[::2], usertemp[1::2]))
    username = usertemp.get('name', 'ec2-user')
    return username