human
Solve the following python programming problem given the following code:
def info_from_instance(context, instance, network_info, system_metadata, **kw) : 
    'Get detailed instance information for an instance which is common to all
    notifications.

    :param:instance: nova.objects.Instance
    :param:network_info: network_info provided if not None
    :param:system_metadata: system_metadata DB entries for the instance,
    if not None

    .. note::

        Currently unused here in trunk, but needed for potential custom
        modifications.

    ' 
    def null_safe_str(s) : 
        return (str (s) if s else '') 
def null_safe_int(s) : 
        return (int (s) if s else '') 
def null_safe_isotime(s) : 
        if isinstance (s, datetime.datetime) : 
            return utils.strtime (s) 
else : 
            return (str (s) if s else '') 
image_ref_url = glance.generate_image_url (instance.image_ref) 
    instance_type = instance.get_flavor () 
    instance_type_name = instance_type.get ('name', '') 
    instance_flavorid = instance_type.get ('flavorid', '') 
    instance_info = dict (tenant_id = instance.project_id, user_id = instance.user_id, instance_id = instance.uuid, display_name = instance.display_name, reservation_id = instance.reservation_id, hostname = instance.hostname, instance_type = instance_type_name, instance_type_id = instance.instance_type_id, instance_flavor_id = instance_flavorid, architecture = instance.architecture, memory_mb = instance.memory_mb, disk_gb = (instance.root_gb + instance.ephemeral_gb), vcpus = instance.vcpus, root_gb = instance.root_gb, ephemeral_gb = instance.ephemeral_gb, host = instance.host, node = instance.node, availability_zone = instance.availability_zone, cell_name = null_safe_str (instance.cell_name), created_at = str (instance.created_at), terminated_at = null_safe_isotime (instance.get ('terminated_at', None)), deleted_at = null_safe_isotime (instance.get ('deleted_at', None)), launched_at = null_safe_isotime (instance.get ('launched_at', None)), image_ref_url = image_ref_url, os_type = instance.os_type, kernel_id =...

    
    

    Fix the buggy line: ip ['vif_mac'] = instance_type ['address']
assistant
#Here is Python code to fix the buggy line: ip ['vif_mac'] = instance_type ['address']
.

ip ['vif_mac'] = vif ['address']