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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 startup_gce_instance(instance_name, project, zone, username, machine_type, image, public_key, disk_name=None):
 """ For now, jclouds is broken for GCE and we will have static slaves in Jenkins. Use this to boot them. """

    log_green("Started...")
    log_yellow("...Creating GCE Jenkins Slave Instance...")
    instance_config = get_gce_instance_config(
        instance_name, project, zone, machine_type, image,
        username, public_key, disk_name
    )
    operation = _get_gce_compute().instances().insert(
        project=project,
        zone=zone,
        body=instance_config
    ).execute()
    result = gce_wait_until_done(operation)
    if not result:
        raise RuntimeError("Creation of VM timed out or returned no result")
    log_green("Instance has booted")