**`` operator, when an attribute
      name is also a Python reserved word, as in ``**{"class":"Customer", "align":"right"}``
    - a list of name-value tuples, as in ``(("ns1:class", "Customer"), ("ns2:align", "right"))``

    For attribute names with a namespace prefix, you must use the second
    form.  Attribute names are matched insensitive to upper/lower case.

    If just testing for ``class`` (with or without a namespace), use
    :class:`with_class`.

    To verify that the attribute exists, but without specifying a value,
    pass ``with_attribute.ANY_VALUE`` as the value.

    Example::

        html = '''
            <div>
            Some text
            <div type="grid">1 4 0 1 0</div>
            <div type="graph">1,3 2,3 1,1</div>
            <div>this has no type</div>
            </div>

        '''
        div,div_end = make_html_tags("div")

        # only match div tag having a type attribute with value "grid"
        div_grid = div().set_parse_action(with_attribute(type="grid"))
        grid_expr = div_grid + SkipTo(div | div_end)("body")
        for grid_header in grid_expr.search_string(html):
            print(grid_header.body)

        # construct a match with any div tag having a type attribute, regardless of the value
        div_any_type = div().set_parse_action(with_attribute(type=with_attribute.ANY_VALUE))
        div_expr = div_any_type + SkipTo(div | div_end)("body")
        for div_header in div_expr.search_string(html):
            print(div_header.body)

    prints::

        1 4 0 1 0

        1 4 0 1 0
        1,3 2,3 1,1
    Nc