How to use the rpg.package_builder.PackageBuilder function in rpg

def test_rpm_build_err_parse(self):
        with self.assertRaises(BuildException) as be:
            PackageBuilder().build_rpm(
                "", "", "", Path(""))
            self.assertEqual(
                sorted(be.errors),
                sorted([text.decode("utf-8")
                        for text in MockedSubprocess.ErrorText]))

def __init__(self):
        self.spec = Spec()
        self.spec.Name = "mock"
        self.spec.Version = "1.0"
        self.spec.Release = "1%{?dist}"
        self.spec.Summary = "Hello World test program"
        self.spec.License = "GPLv2"
        self.spec.Source = "mock-1.0.tar.gz"
        self.spec.description = "Hello World C project for testing RPG."
        self.spec.prep = r'%autosetup'
        self.spec.build = "make"
        self.sack = self.load_dnf_sack()
        self._package_builder = PackageBuilder()
        self.conf = FakeConf()
        self.load_plugins()

def setUpClass(cls):
        cls.distro = "fedora-22"
        cls.arch = "x86_64"
        cls.package_builder = PackageBuilder()
        cls.package_builder.fetch_repos(cls.distro, cls.arch)

def __init__(self):
        self._package_builder = PackageBuilder()
        self.spec = Spec()
        self.spec.Name = "hello"
        self.spec.Version = "1.4"
        self.spec.Release = "1%{?dist}"
        self.spec.Summary = "Hello World test program"
        self.spec.License = "GPLv2"
        self.spec.Source = "hello-1.4.tar.gz"
        self.spec.description = "Hello World C project for testing RPG."
        self.spec.prep = r'%autosetup'
        self.spec.build = "make"
        self.spec.install = r"make install DESTDIR=%{RPM_BUILD_ROOT}"

def setUpClass(cls):
        PackageBuilder.fetch_repos("fedora-22", "x86_64")

def __init__(self):
        self.conf = Conf()
        self._setup_logging()
        self._project_builder = ProjectBuilder()
        self.spec = Spec()
        self.sack = None
        self._package_builder = PackageBuilder()