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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def serialize_elements(document, elements, options=None):
 """Serialize list of elements into HTML string. :Args: - document (:class:`ooxml.doc.Document`):
 Document object - elements (list):
 List of elements - options (dict):
 Optional dictionary with :class:`Context` options :Returns: Returns HTML representation of the document. """
    
    ctx = Context(document, options)

    tree_root = root = etree.Element('div')

    for elem in elements:
        _ser = ctx.get_serializer(elem)

        if _ser:
            root = _ser(ctx, document, elem, root)

    # TODO:
    # - create footnotes now

    return etree.tostring(tree_root, pretty_print=ctx.options.get('pretty_print', True), encoding="utf-8", xml_declaration=False)