def prepare_class(name, bases=(), kwds=None):
    if kwds is None:
        kwds = {}
    else:
        kwds = dict(kwds) # Don't alter the provided mapping
    if 'metaclass' in kwds:
        meta = kwds.pop('metaclass')
    else:
        if bases:
            meta = type(bases[0])
        else:
            meta = type
    if isinstance(meta, type):
        # when meta is a type, we first determine the most-derived metaclass
        # instead of invoking the initial candidate directly
        meta = _calculate_meta(meta, bases)
    if hasattr(meta, '__prepare__'):
        ns = meta.__prepare__(name, bases, **kwds)
    else:
        ns = {}
    return meta, ns, kwds
Return the motif length from motif matrix data file.
dataset/ETHPy150Open amrdraz/kodr/app/brython/www/src/Lib/types.py/prepare_class--crossover with--dataset/ETHPy150Open taoliu/taolib/Motif/__init__.py/mlen