__init__.py 文件源码

def column_width(text):
    """Return the column width of text.

    Correct ``len(text)`` for wide East Asian and combining Unicode chars.
    """
    if isinstance(text, str) and sys.version_info < (3,0):
        return len(text)
    try:
        width = sum([east_asian_widths[unicodedata.east_asian_width(c)]
                     for c in text])
    except AttributeError:  # east_asian_width() New in version 2.4.
        width = len(text)
    # correction for combining chars:
    width -= len(find_combining_chars(text))
    return width