* @param size The size.
     */
    public void setSize(final int size) {
        this.size = size;
    }

    /**
     * Sets the seed for random function.
     * @param seed The seed.
     */
    public void setSeed(final String seed) {
        this.seed = seed;
    }

    /**
     * Sets the window size for rescoring.
     * @param windowSize The window size.
     */

        request.addLanguage(lang);
        return this;
    }

    /**
     * Sets the seed for random function.
     * @param seed The seed.
     * @return This builder instance.
     */
    public PopularWordsRequestBuilder setSeed(final String seed) {
        request.setSeed(seed);
        return this;
    }

    /**
     * Sets the window size for rescoring.

     *
     * This method removes characters that are not allowed in XML documents
     * according to the XML 1.0 specification. Valid characters include:
     * - Tab (0x9)
     * - Line feed (0xA)
     * - Carriage return (0xD)
     * - Any character between 0x20 and 0xD7FF
     * - Any character between 0xE000 and 0xFFFD
     * - Any character between 0x10000 and 0x10FFFF
     *