human
I wrote the below code

    if (not isinstance(version, (tuple, six.string_types, salt.version.SaltStackVersion))):
        raise RuntimeError("The    'version'    argument    should    be    passed    as    a    tuple,    string    or    an    instance    of    'salt.version.SaltStackVersion'.")
    elif isinstance(version, tuple):
        version = salt.version.SaltStackVersion(*version)
    elif isinstance(version, six.string_types):
        version = salt.version.SaltStackVersion.from_name(version)
    if (stacklevel is None):
        stacklevel = 2
    if (_version_info_ is None):
        _version_info_ = salt.version.__version_info__
    _version_ = salt.version.SaltStackVersion(*_version_info_)
    if (_version_ >= version):
        import inspect
        caller = inspect.getframeinfo(sys._getframe((stacklevel - 1)))
        raise RuntimeError("The    warning    triggered    on    filename    '{filename}',    line    number    {lineno},    is    supposed    to    be    shown    until    version    {until_version}    is    released.    Current    version    is    now    {salt_version}.    Please    remove    the    warning.".format(filename=caller.filename, lineno=caller.lineno, until_version=version.formatted_version, salt_version=_version_.formatted_version))
    if (_dont_call_warnings is False):
        def _formatwarning(message, category, filename, lineno, line=None):
            "\n                                                Replacement    for    warnings.formatwarning    that    disables    the    echoing    of\n                                                the    'line'    parameter.\n                                                "
            return '{0}:{1}:    {2}:    {3}\n'.format(filename, lineno, category.__name__, message)
        saved = warnings.formatwarning
        warnings.formatwarning = _formatwarning
        warnings.warn(message.format(version=version.formatted_version), category, stacklevel=stacklevel)
        warnings.formatwarning = saved

What's a good function header?
assistant
#Here's a good function header.

def warn_until(version, message, category=DeprecationWarning, stacklevel=None, _version_info_=None, _dont_call_warnings=False):