public function is_ready() {
        if (empty($this->pathtopython)) {
            $settingurl = new \moodle_url('/admin/settings.php', array('section' => 'systempaths'));
            return get_string('pythonpathnotdefined', 'mlbackend_python', $settingurl->out());
        }

        // Check the installed pip package version.
        $cmd = "{$this->pathtopython} -m moodlemlbackend.version";

        $output = null;
        $exitcode = null;
        // Execute it sending the standard error to $output.
        $result = exec($cmd . ' 2>&1', $output, $exitcode);

        $vercheck = self::check_pip_package_version($result);

        if ($vercheck === 0) {
            return true;
        }

        if ($exitcode != 0) {
            return get_string('pythonpackagenotinstalled', 'mlbackend_python', $cmd);
        }

        if ($result) {
            $a = [
                'installed' => $result,
                'required' => self::REQUIRED_PIP_PACKAGE_VERSION,
            ];

            if ($vercheck < 0) {
                return get_string('packageinstalledshouldbe', 'mlbackend_python', $a);

            } else if ($vercheck > 0) {
                return get_string('packageinstalledtoohigh', 'mlbackend_python', $a);
            }
        }

        return get_string('pythonpackagenotinstalled', 'mlbackend_python', $cmd);
    }