How to use the hdmf.build.BuildManager function in hdmf

if not os.path.isfile(path):
            print("The file {} does not exist.".format(path), file=sys.stderr)
            ret = 1
            continue

        if args.cached_namespace:
            catalog = NamespaceCatalog(NWBGroupSpec, NWBDatasetSpec, NWBNamespace)
            ns_deps = NWBHDF5IO.load_namespaces(catalog, path)
            s = set(ns_deps.keys())       # determine which namespaces are the most
            for k in ns_deps:             # specific (i.e. extensions) and validate
                s -= ns_deps[k].keys()    # against those
            namespaces = list(sorted(s))
            if len(namespaces) > 0:
                tm = TypeMap(catalog)
                manager = BuildManager(tm)
                specloc = "cached namespace information"
            else:
                manager = None
                namespaces = available_namespaces()
                specloc = "pynwb namespace information"
                print("The file {} has no cached namespace information. "
                      "Falling back to {}.".format(path, specloc), file=sys.stderr)
        elif args.nspath:
            catalog = NamespaceCatalog(NWBGroupSpec, NWBDatasetSpec, NWBNamespace)
            namespaces = catalog.load_namespaces(args.nspath)

            if len(namespaces) == 0:
                print("Could not load namespaces from file {}.".format(args.nspath), file=sys.stderr)
                sys.exit(1)

            tm = TypeMap(catalog)

else:
                manager = None
                namespaces = available_namespaces()
                specloc = "pynwb namespace information"
                print("The file {} has no cached namespace information. "
                      "Falling back to {}.".format(path, specloc), file=sys.stderr)
        elif args.nspath:
            catalog = NamespaceCatalog(NWBGroupSpec, NWBDatasetSpec, NWBNamespace)
            namespaces = catalog.load_namespaces(args.nspath)

            if len(namespaces) == 0:
                print("Could not load namespaces from file {}.".format(args.nspath), file=sys.stderr)
                sys.exit(1)

            tm = TypeMap(catalog)
            manager = BuildManager(tm)
            specloc = "--nspath namespace information"
        else:
            manager = None
            namespaces = available_namespaces()
            specloc = "pynwb namespace information"

        if args.ns:
            if args.ns in namespaces:
                namespaces = [args.ns]
            else:
                print("The namespace {} could not be found in {}.".format(args.ns, specloc), file=sys.stderr)
                ret = 1
                continue

        with NWBHDF5IO(path, mode='r', manager=manager) as io:
            for ns in namespaces:

def get_manager(**kwargs):
    '''
    Get a BuildManager to use for I/O using the given extensions. If no extensions are provided,
    return a BuildManager that uses the core namespace
    '''
    type_map = call_docval_func(get_type_map, kwargs)
    return BuildManager(type_map)

            {'name': 'manager', 'type': BuildManager, 'doc': 'the BuildManager to use for I/O', 'default': None},
            {'name': 'extensions', 'type': (str, TypeMap, list),
             'doc': 'a path to a namespace, a TypeMap, or a list consisting paths \
             to namespaces and TypeMaps', 'default': None},
            {'name': 'file', 'type': h5py.File, 'doc': 'a pre-existing h5py.File object', 'default': None},
            {'name': 'comm', 'type': "Intracomm", 'doc': 'the MPI communicator to use for parallel I/O',
             'default': None})
    def __init__(self, **kwargs):
        path, mode, manager, extensions, load_namespaces, file_obj, comm =\
            popargs('path', 'mode', 'manager', 'extensions', 'load_namespaces', 'file', 'comm', kwargs)
        if load_namespaces:
            if manager is not None:
                warn("loading namespaces from file - ignoring 'manager'")
            if extensions is not None:
                warn("loading namespaces from file - ignoring 'extensions' argument")
            if 'w' in mode:
                raise ValueError("cannot load namespaces from file when writing to it")

warn("loading namespaces from file - ignoring 'manager'")
            if extensions is not None:
                warn("loading namespaces from file - ignoring 'extensions' argument")
            if 'w' in mode:
                raise ValueError("cannot load namespaces from file when writing to it")

            # XXX: Leaving this here in case we want to revert to this strategy for
            #      loading cached namespaces
            # ns_catalog = NamespaceCatalog(NWBGroupSpec, NWBDatasetSpec, NWBNamespace)
            # super(NWBHDF5IO, self).load_namespaces(ns_catalog, path)
            # tm = TypeMap(ns_catalog)
            # tm.copy_mappers(get_type_map())

            tm = get_type_map()
            super(NWBHDF5IO, self).load_namespaces(tm, path)
            manager = BuildManager(tm)
        else:
            if manager is not None and extensions is not None:
                raise ValueError("'manager' and 'extensions' cannot be specified together")
            elif extensions is not None:
                manager = get_manager(extensions=extensions)
            elif manager is None:
                manager = get_manager()
        super(NWBHDF5IO, self).__init__(path, manager=manager, mode=mode, file=file_obj, comm=comm)

            {"name": "manager", "type": BuildManager, "doc": "the BuildManager used for managing this build"},
            returns='the value of the attribute')
    def get_attr_value(self, **kwargs):
        ''' Get the value of the attribute corresponding to this spec from the given container '''
        spec, container, manager = getargs('spec', 'container', 'manager', kwargs)
        attr_value = super(DynamicTableMap, self).get_attr_value(spec, container, manager)
        if attr_value is None and spec.name in container:
            if spec.neurodata_type_inc == 'VectorData':
                attr_value = container[spec.name]
                if isinstance(attr_value, VectorIndex):
                    attr_value = attr_value.target
            elif spec.neurodata_type_inc == 'DynamicTableRegion':
                attr_value = container[spec.name]
                if attr_value.table is None:
                    msg = "empty or missing table for DynamicTableRegion '%s' in DynamicTable '%s'" %\
                          (attr_value.name, container.name)
                    raise ValueError(msg)