Cannot save figure as svg

Hello stevengj and all the gang:

This may be an issue on an update on matplotlib and not here, but I do not know for sure. I have recently created some "image" (colormaps) plots on PyPlot and saved them as svg, no problem. In the same Jupyter notebook, then, I created a more complex figure, that overlays line plots over the colormap and puts various custom labels. I can save the picture as png and eps, but not as svg. I get a very unreadable error message:

```
LoadError: PyError (:PyObject_Call)
TypeError("'H�E�I�\x07H��H[A\\A]A^A_]�H���H�\x05/��\x01H�@\x08H�E�H�\x05(��\x01H�E�1�L���\x02' object is not callable",)
File "/usr/lib64/python3.4/site-packages/matplotlib/pyplot.py", line 688, in savefig
res = fig.savefig(*args, **kwargs)
```

and continues for various lines on the same vein...

Okey, new detail: I cannot save any longer the simpler figures as svg also. I swear I did not "upgraded" anything in the middle...

Start by reproducing the reported behavior in the same Jupyter notebook, comparing SVG with PNG and EPS output through PyPlot and matplotlib/pyplot.py savefig. Capture the complete traceback and environment details; done means identifying a reproducible cause or confirming whether SVG export works consistently.

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