'Probe whether a contains b'

@staticmethod
def _probe_contains(a, b):

    if (a is None):
        return False
    try:
        if isinstance(a, basestring):
            return (str(b) in a)
        elif isinstance(a, (list, tuple, set)):
            if isinstance(b, (list, tuple, set)):
                convert = S3TypeConverter.convert
                found = True
                for _b in b:
                    if (_b not in a):
                        found = False
                        for _a in a:
                            try:
                                if (convert(_a, _b) == _a):
                                    found = True
                                    break
                            except (TypeError, ValueError):
                                continue
                    if (not found):
                        break
                return found
            else:
                return (b in a)
        else:
            return (str(b) in str(a))
    except:
        return False
