Compute matches when text contains a dot.

        Assuming the text is of the form NAME.NAME....[NAME], and is
        evaluable in self.namespace, it will be evaluated and its attributes
        (as revealed by dir()) are used as possible completions.  (For class
        instances, class members are also considered.)

        WARNING: this can still invoke arbitrary C code, if an object
        with a __getattr__ hook is evaluated.

def attr_matches(self, text):
        """Compute matches when text contains a dot.

        Assuming the text is of the form NAME.NAME....[NAME], and is
        evaluable in self.namespace, it will be evaluated and its attributes
        (as revealed by dir()) are used as possible completions.  (For class
        instances, class members are also considered.)

        WARNING: this can still invoke arbitrary C code, if an object
        with a __getattr__ hook is evaluated.

        """
        import re
        m = re.match(r"(\w+(\.\w+)*)\.(\w*)", text)
        if not m:
            return []
        expr, attr = m.group(1, 3)
        try:
            thisobject = eval(expr, self.namespace)
        except Exception:
            return []

        # get the content of the object, except __builtins__
        words = set(dir(thisobject))
        words.discard("__builtins__")

        if hasattr(thisobject, '__class__'):
            words.add('__class__')
            words.update(get_class_members(thisobject.__class__))
        matches = []
        n = len(attr)
        for word in words:
            if word[:n] == attr:
                try:
                    val = getattr(thisobject, word)
                except Exception:
                    continue  # Exclude properties that are not set
                word = self._callable_postfix(val, "%s.%s" % (expr, word))
                matches.append(word)
        matches.sort()
        return matches