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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 up(ctx, instance_id):
 """Start EC2 instance"""

    session = create_session(ctx.obj['AWS_PROFILE_NAME'])
    ec2 = session.resource('ec2')
    try:
        instance = ec2.Instance(instance_id)
        instance.start()
    except botocore.exceptions.ClientError as e:
        click.echo("Invalid instance ID {0} ({1})".format(instance_id, e), err=True)
        sys.exit(2)