def describe_filter_method(filter_by):
        if callable(filter_by):
            return "matching a function called {}".format(filter_by.__name__)
        if isinstance(filter_by, six.string_types):
            return "containing the string {!r}".format(filter_by)
        if have_ham and isinstance(filter_by, hamcrest.matcher.Matcher):
            return "containing "+str(filter_by)
        if isinstance(filter_by, REGEX_PATTERN_TYPE):
            return "matching the regex {!r}".format(filter_by.pattern)
        else:
            return "which we're surprised we found at all"