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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 _move_node_file(path, old_id, new_id):
 """ Move the files from a node when changing his id :param path: Path of the project :param old_id: ID before change :param new_id: New node UUID """

    root = os.path.join(path, "project-files")
    if os.path.exists(root):
        for dirname in os.listdir(root):
            module_dir = os.path.join(root, dirname)
            if os.path.isdir(module_dir):
                node_dir = os.path.join(module_dir, old_id)
                if os.path.exists(node_dir):
                    shutil.move(node_dir, os.path.join(module_dir, new_id))