_lib.py 文件源码

def wrapped_ndpointer(*args, **kwargs):
    """
    Specifies an ndpointer type that wraps numpy.ctypeslib.ndpointer and
    allows a value of None to be passed to an argument of that type.

    Taken from http://stackoverflow.com/questions/32120178
    """
    if sys.version_info < (3,):
        if 'flags' in kwargs:
            kwargs['flags'] = tuple(
                f.encode('ascii') for f in kwargs['flags'])

    base = ndpointer(*args, **kwargs)

    def from_param(cls, obj):
        if obj is None:
            return obj
        return base.from_param(obj)

    return type(base.__name__, (base,),
                {'from_param': classmethod(from_param)})