demo_python/d_str.py -- string.maketrans, string.translate
demo_python/d_str.py ischinese, filter_ch; char.py collection of chars; d_text.py read_text and write_text using unicode
demo_python/d_text.py read_text and write_text using unicode
demo_python/char.py collection of chars;
demo_python/d_file.py using codecs read utf-8 chinese streams in files
tmp