is a file, or if must_be_file is True and the child is a directory,
I raise ChildOfWrongTypeError."""
- def create_subdirectory(name, initial_children={}, overwrite=True, metadata=None):
+ def create_subdirectory(name, initial_children={}, overwrite=True,
+ mutable=True, mutable_version=None, metadata=None):
"""I create and attach a directory at the given name. The new
directory can be empty, or it can be populated with children
according to 'initial_children', which takes a dictionary in the same