def _help(*args, **kws):
    helper.buffer = []
    _larch = kws.get('_larch', None)
    if helper._larch is None and _larch is not None:
        helper._larch = _larch
    if args == ('',):
        args = ('help',)
    if helper._larch is None:
        helper.addtext('cannot start help system!')
    else:
        for a in args:
            helper.help(a)

    if helper._larch is not None:
        helper._larch.writer.write("%s\n" % helper.getbuffer())
    else:
        return helper.getbuffer()
show help on topic or object
dataset/ETHPy150Open xraypy/xraylarch/lib/builtins.py/_help