def _normalize(options):
    """Return correct kwargs for setup() from provided options-dict.
    """
    retval = {
        key.replace("-", "_"): value for key, value in options.items()
    }

    # Classifiers
    value = retval.pop("classifiers", None)
    if value and isinstance(value, str):
        classifiers = value.splitlines()
        while "" in classifiers:
            classifiers.remove("")
        retval["classifiers"] = classifiers

    # Long description from file
    description_file = retval.pop("long_description_file", None)
    if description_file:
        try:
            with open(description_file) as fdesc:
                retval["long_description"] = fdesc.read()
        except IOError:
            retval["long_description"] = "Read the accompanying {}".format(
                description_file
            )

    return retval