from matplotlib.tests.test_pickle import recursive_pickle
f = figure()
plot(range(10))
f.tight_layout(pad=0.3)
recursive_pickle(f)

<RendererAgg object at 0x3da7508>
Failed to pickle attribute "_renderer" in (attribute "_renderer" in (attribute "label" in
(list/tuple item #0 in (attribute "majorTicks" in (attribute "xaxis" in (list/tuple item #1
in (list/tuple item #1 in (list/tuple item #0 in (attribute "_elements" in (attribute
"_axstack" in (top level object))))))))))).
 Type: <type 'RendererAgg'>. Traceback follows:
---------------------------------------------------------------------------
UnpickleableError                         Traceback (most recent call last)
<ipython-input-1-34aaa9934d37> in <module>()
      3 plot(range(10))
      4 f.tight_layout(pad=1.0)
----> 5 recursive_pickle(f)

/home/mspacek/src/matplotlib/lib/matplotlib/tests/test_pickle.pyc in recursive_pickle(top_obj)
     88 #        print('trying %s' % location)
     89         try:
---> 90             pickle.dump(obj, BytesIO(), pickle.HIGHEST_PROTOCOL)
     91         except Exception, err:
     92             print(obj)

UnpickleableError: Cannot pickle <type 'RendererAgg'> objects