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<div class="menucontainer">
    <ul>
        <li class="parent_menu"><a href="#">Home</a>

        </li>
        <li class="parent_menu"><a href="#">About Us</a>

        </li>
        <li class="parent_menu has_child"><a href="#">Product</a>

            <ul>
                <li class="child_menu has_child_sub"><a href="#">Product 1</a>

                </li>
                <li class="child_menu"><a href="#">Product 2</a>

                </li>
                <li class="child_menu"><a href="#">Product 3</a>

                </li>
            </ul>
        </li>
        <li class="parent_menu has_child"><a href="#">Services</a>

            <ul>
                <li class="child_menu"><a href="#">Product 1</a>

                </li>
                <li class="child_menu"><a href="#">Product 2</a>

                </li>
                <li class="child_menu"><a href="#">Product 3</a>

                </li>
            </ul>
        </li>
        <li class="parent_menu"><a href="#">Contact Us</a>

        </li>
    </ul>
</div>