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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 get_network_folder(dc_ref):
    '''
    Retrieves the network folder of a datacenter
    '''
    dc_name = get_managed_object_name(dc_ref)
    log.trace('Retrieving network folder in datacenter \'%s\'', dc_name)
    service_instance = get_service_instance_from_managed_object(dc_ref)
    traversal_spec = vmodl.query.PropertyCollector.TraversalSpec(
        path='networkFolder',
        skip=False,
        type=vim.Datacenter)
    entries = get_mors_with_properties(service_instance,
                                       vim.Folder,
                                       container_ref=dc_ref,
                                       property_list=['name'],
                                       traversal_spec=traversal_spec)
    if not entries:
        raise salt.exceptions.VMwareObjectRetrievalError(
            'Network folder in datacenter \'{0}\' wasn\'t retrieved'
            ''.format(dc_name))
    return entries[0]['object']