How to use the scons.scons-local-250.SCons.Tool.packaging.rpm.SimpleTagCompiler function in SCons

# Default prep, build, install and clean rules
    # TODO: optimize those build steps, to not compile the project a second time
    if 'X_RPM_PREP' not in spec:
        spec['X_RPM_PREP'] = '[ -n "$RPM_BUILD_ROOT" -a "$RPM_BUILD_ROOT" != / ] && rm -rf "$RPM_BUILD_ROOT"' + '\n%setup -q'

    if 'X_RPM_BUILD' not in spec:
        spec['X_RPM_BUILD'] = '[ ! -e "$RPM_BUILD_ROOT" -a "$RPM_BUILD_ROOT" != / ] && mkdir "$RPM_BUILD_ROOT"'

    if 'X_RPM_INSTALL' not in spec:
        spec['X_RPM_INSTALL'] = 'scons --install-sandbox="$RPM_BUILD_ROOT" "$RPM_BUILD_ROOT"'

    if 'X_RPM_CLEAN' not in spec:
        spec['X_RPM_CLEAN'] = '[ -n "$RPM_BUILD_ROOT" -a "$RPM_BUILD_ROOT" != / ] && rm -rf "$RPM_BUILD_ROOT"'

    str = str + SimpleTagCompiler(optional_sections, mandatory=0).compile( spec )

    return str

def build_specfile_header(spec):
    """ Builds all sections but the %file of a rpm specfile
    """
    str = ""

    # first the mandatory sections
    mandatory_header_fields = {
        'NAME'           : '%%define name %s\nName: %%{name}\n',
        'VERSION'        : '%%define version %s\nVersion: %%{version}\n',
        'PACKAGEVERSION' : '%%define release %s\nRelease: %%{release}\n',
        'X_RPM_GROUP'    : 'Group: %s\n',
        'SUMMARY'        : 'Summary: %s\n',
        'LICENSE'        : 'License: %s\n', }

    str = str + SimpleTagCompiler(mandatory_header_fields).compile( spec )

    # now the optional tags
    optional_header_fields = {
        'VENDOR'              : 'Vendor: %s\n',
        'X_RPM_URL'           : 'Url: %s\n',
        'SOURCE_URL'          : 'Source: %s\n',
        'SUMMARY_'            : 'Summary(%s): %s\n',
        'X_RPM_DISTRIBUTION'  : 'Distribution: %s\n',
        'X_RPM_ICON'          : 'Icon: %s\n',
        'X_RPM_PACKAGER'      : 'Packager: %s\n',
        'X_RPM_GROUP_'        : 'Group(%s): %s\n',

        'X_RPM_REQUIRES'      : 'Requires: %s\n',
        'X_RPM_PROVIDES'      : 'Provides: %s\n',
        'X_RPM_CONFLICTS'     : 'Conflicts: %s\n',
        'X_RPM_BUILDREQUIRES' : 'BuildRequires: %s\n',

def build_specfile_header(spec):
    """ Builds all sections but the %file of a rpm specfile
    """
    str = ""

    # first the mandatory sections
    mandatory_header_fields = {
        'NAME'           : '%%define name %s\nName: %%{name}\n',
        'VERSION'        : '%%define version %s\nVersion: %%{version}\n',
        'PACKAGEVERSION' : '%%define release %s\nRelease: %%{release}\n',
        'X_RPM_GROUP'    : 'Group: %s\n',
        'SUMMARY'        : 'Summary: %s\n',
        'LICENSE'        : 'License: %s\n', }

    str = str + SimpleTagCompiler(mandatory_header_fields).compile( spec )

    # now the optional tags
    optional_header_fields = {
        'VENDOR'              : 'Vendor: %s\n',
        'X_RPM_URL'           : 'Url: %s\n',
        'SOURCE_URL'          : 'Source: %s\n',
        'SUMMARY_'            : 'Summary(%s): %s\n',
        'X_RPM_DISTRIBUTION'  : 'Distribution: %s\n',
        'X_RPM_ICON'          : 'Icon: %s\n',
        'X_RPM_PACKAGER'      : 'Packager: %s\n',
        'X_RPM_GROUP_'        : 'Group(%s): %s\n',

        'X_RPM_REQUIRES'      : 'Requires: %s\n',
        'X_RPM_PROVIDES'      : 'Provides: %s\n',
        'X_RPM_CONFLICTS'     : 'Conflicts: %s\n',
        'X_RPM_BUILDREQUIRES' : 'BuildRequires: %s\n',

'X_RPM_CONFLICTS'     : 'Conflicts: %s\n',

        # internal use
        'X_RPM_BUILDROOT'     : 'BuildRoot: %s\n', }

    # fill in default values:
    # Adding a BuildRequires renders the .rpm unbuildable under System, which
    # are not managed by rpm, since the database to resolve this dependency is
    # missing (take Gentoo as an example)
#    if not s.has_key('x_rpm_BuildRequires'):
#        s['x_rpm_BuildRequires'] = 'scons'

    if 'X_RPM_BUILDROOT' not in spec:
        spec['X_RPM_BUILDROOT'] = '%{_tmppath}/%{name}-%{version}-%{release}'

    str = str + SimpleTagCompiler(optional_header_fields, mandatory=0).compile( spec )
    return str

def build_specfile_sections(spec):
    """ Builds the sections of a rpm specfile.
    """
    str = ""

    mandatory_sections = {
        'DESCRIPTION'  : '\n%%description\n%s\n\n', }

    str = str + SimpleTagCompiler(mandatory_sections).compile( spec )

    optional_sections = {
        'DESCRIPTION_'        : '%%description -l %s\n%s\n\n',
        'CHANGELOG'           : '%%changelog\n%s\n\n',
        'X_RPM_PREINSTALL'    : '%%pre\n%s\n\n',
        'X_RPM_POSTINSTALL'   : '%%post\n%s\n\n',
        'X_RPM_PREUNINSTALL'  : '%%preun\n%s\n\n',
        'X_RPM_POSTUNINSTALL' : '%%postun\n%s\n\n',
        'X_RPM_VERIFY'        : '%%verify\n%s\n\n',

        # These are for internal use but could possibly be overridden
        'X_RPM_PREP'          : '%%prep\n%s\n\n',
        'X_RPM_BUILD'         : '%%build\n%s\n\n',
        'X_RPM_INSTALL'       : '%%install\n%s\n\n',
        'X_RPM_CLEAN'         : '%%clean\n%s\n\n',
        }

'PACKAGING_X_RPM_DOCDIR'     : '%%docdir %s',
        'PACKAGING_X_RPM_GHOST'      : '%%ghost %s', }

    for file in files:
        # build the tagset
        tags = {}
        for k in supported_tags.keys():
            try:
                v = file.GetTag(k)
                if v:
                    tags[k] = v
            except AttributeError:
                pass

        # compile the tagset
        str = str + SimpleTagCompiler(supported_tags, mandatory=0).compile( tags )

        str = str + ' '
        str = str + file.GetTag('PACKAGING_INSTALL_LOCATION')
        str = str + '\n\n'

    return str

def build_specfile_sections(spec):
    """ Builds the sections of a rpm specfile.
    """
    str = ""

    mandatory_sections = {
        'DESCRIPTION'  : '\n%%description\n%s\n\n', }

    str = str + SimpleTagCompiler(mandatory_sections).compile( spec )

    optional_sections = {
        'DESCRIPTION_'        : '%%description -l %s\n%s\n\n',
        'CHANGELOG'           : '%%changelog\n%s\n\n',
        'X_RPM_PREINSTALL'    : '%%pre\n%s\n\n',
        'X_RPM_POSTINSTALL'   : '%%post\n%s\n\n',
        'X_RPM_PREUNINSTALL'  : '%%preun\n%s\n\n',
        'X_RPM_POSTUNINSTALL' : '%%postun\n%s\n\n',
        'X_RPM_VERIFY'        : '%%verify\n%s\n\n',

        # These are for internal use but could possibly be overridden
        'X_RPM_PREP'          : '%%prep\n%s\n\n',
        'X_RPM_BUILD'         : '%%build\n%s\n\n',
        'X_RPM_INSTALL'       : '%%install\n%s\n\n',
        'X_RPM_CLEAN'         : '%%clean\n%s\n\n',
        }