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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 root2hdf5(rfile, hfile, rpath='', entries=-1, userfunc=None, show_progress=False, ignore_exception=False, **kwargs):
 """ Convert all trees in a ROOT file into tables in an HDF5 file. Parameters rfile : string or asrootpy'd ROOT File A ROOT File handle or string path to an existing ROOT file. hfile : string or PyTables HDF5 File A PyTables HDF5 File handle or string path to an existing HDF5 file. rpath : string, optional (default='') Top level path to begin traversal through the ROOT file. By default convert everything in and below the root directory. entries : int, optional (default=-1) The number of entries to read at once while converting a ROOT TTree into an HDF5 table. By default read the entire TTree into memory (this may not be desired if your TTrees are large). userfunc : callable, optional (default=None) A function that will be called on every tree and that must return a tree or list of trees that will be converted instead of the original tree. show_progress : bool, optional (default=False) If True, then display and update a progress bar on stdout as each tree is converted. ignore_exception : bool, optional (default=False) If True, then ignore exceptions raised in converting trees and instead skip such trees. kwargs : dict, optional Additional keyword arguments for the tree2array function. """

    own_rootfile = False
    if isinstance(rfile, string_types):
        rfile = root_open(rfile)
        own_rootfile = True

    own_h5file = False
    if isinstance(hfile, string_types):
        hfile = tables_open(filename=hfile, mode="w", title="Data")
        own_h5file = True

    for dirpath, dirnames, treenames in rfile.walk(
            rpath, class_ref=QROOT.TTree):

        # skip directories w/o trees
        if not treenames:
            continue

        treenames.sort()

        group_where = '/' + os.path.dirname(dirpath)
        group_name = os.path.basename(dirpath)

        if not group_name:
            group = hfile.root
        elif TABLES_NEW_API:
            group = hfile.create_group(group_where, group_name,
                                       createparents=True)
        else:
            group = hfile.createGroup(group_where, group_name)

        ntrees = len(treenames)
        log.info(
            "Will convert {0:d} tree{1} in {2}".format(
                ntrees, 's' if ntrees != 1 else '',
                os.path.join(group_where, group_name)))

        for treename in treenames:

            input_tree = rfile.Get(os.path.join(dirpath, treename))

            if userfunc is not None:
                tmp_file = TemporaryFile()
                # call user-defined function on tree and get output trees
                log.info("Calling user function on tree '{0}'".format(
                    input_tree.GetName()))
                trees = userfunc(input_tree)

                if not isinstance(trees, list):
                    trees = [trees]

            else:
                trees = [input_tree]
                tmp_file = None

            for tree in trees:
                try:
                    tree2hdf5(tree, hfile, group=group,
                              entries=entries,
                              show_progress=show_progress,
                              **kwargs)
                except Exception as e:
                    if ignore_exception:
                        log.error("Failed to convert tree '{0}': {1}".format(
                            tree.GetName(), str(e)))
                    else:
                        raise

            input_tree.Delete()

            if userfunc is not None:
                for tree in trees:
                    tree.Delete()
                tmp_file.Close()

    if own_h5file:
        hfile.close()
    if own_rootfile:
        rfile.Close()