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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 mkdir(self, name=None, parents=False, mode=0o777):
 """Creates that directory, or a directory under this one. ``path.mkdir(name)`` is a shortcut for ``(path/name).mkdir()``. :param name: Path component to append to this path before creating the directory. :param parents: If True, missing directories leading to the path will be created too, recursively. If False (the default), the parent of that path needs to exist already. :param mode: Permissions associated with the directory on creation, without race conditions. """

        if name is not None:
            return (self / name).mkdir(parents=parents, mode=mode)
        if self.exists():
            return
        if parents:
            os.makedirs(self.path, mode)
        else:
            os.mkdir(self.path, mode)
        return self