Generating new user functions load_xyz() and __parse_models_xyz().
This is Han's patch https://gna.org/task/download.php?file_id=13247 attached to the task
http://gna.org/task/?7404.
New user functions load_xyz() and __parse_models_xyz() were generated in
generic_fns/structures/internal.py based on the functions load_pdb() and __parse_models().
