No way to pass arbitrary predicate to .click / .submit methods

[jjlee]

This should result in the first button being clicked:

import mechanize
browser = mechanize.Browser()
browser.set_response(mechanize.make_response(
        """\
<button type="submit" name="action" value="publish">Publish</button>
<button type="submit" name="action" value="preview">Preview</button>
""",
        [("Content-Type", "text/html")],
        "http://example.com/", 200, "OK"))
form = browser.global_form()
form.click(predicate=lambda control: control.name == "publish")