'Separrates valid samtools key/value pair options from a dictionary and
returns both as a 2-tuple.'

@classmethod
def extract_options_from_dict(cls, dictionary):

    options_dict = {}
    new_kwargs = {}
    for (key, value) in dictionary.items():
        if (key in cls.FLAGS_W_ARGS):
            options_dict[key] = value
        else:
            new_kwargs[key] = value
    return (options_dict, new_kwargs)
