def reset() ->None:
    """Reset all wdom objects.

    This function clear all connections, elements, and resistered custom
    elements. This function also makes new document/application and set them.
    """
    from wdom.document import get_new_document, set_document
    from wdom.element import Element
    from wdom.server import _tornado
    from wdom.window import customElements
    set_document(get_new_document())
    _tornado.connections.clear()
    _tornado.set_application(_tornado.Application())
    Element._elements_with_id.clear()
    Element._element_buffer.clear()
    customElements.reset()
