def METHOD_NAME(self):
    latest_ybc_pkg = self.identify_latest_pkg(PV_CONTROLLER_DIR + "/tmp")
    # latest_ybc_pkg is the latest package among the all the packages in the
    # PV_CONTROLLER_DIR + "/tmp" directory.
    # ybc-1.0.0-b9-linux-x86_64.tar.gz is an example of latest_ybc_pkg if
    # there are ybc packages in the PV_CONTROLLER_DIR + "/tmp" directory. If the
    # directory is empty, then latest_ybc_pkg is empty.
    # ybc-1.0.0-b9-linux-x86_64 is an example of latest_ybc_prefix for the
    # above latest_ybc_pkg
    if latest_ybc_pkg:
        latest_ybc_prefix = latest_ybc_pkg[0:-7]
        tar = tarfile.open(PV_CONTROLLER_DIR + "/tmp/" + latest_ybc_pkg)
        tar.extractall(PV_CONTROLLER_DIR)
        self.move_contents(PV_CONTROLLER_DIR + "/" + latest_ybc_prefix + "/bin",
                           PV_CONTROLLER_DIR + "/bin")
        shutil.rmtree(PV_CONTROLLER_DIR + "/" + latest_ybc_prefix)