Traceback (most recent call last):
  File "script.py", line 31, in <module>
    fig.savefig('asd.pdf')
  File "/Users/Damon/python/lib/matplotlib/figure.py", line 1084, in savefig
    self.canvas.print_figure(*args, **kwargs)
  File "/Users/Damon/python/lib/matplotlib/backend_bases.py", line 1961, in print_figure
    **kwargs)
  File "/Users/Damon/python/lib/matplotlib/backends/backend_pdf.py", line 2156, in print_pdf
    self.figure.draw(renderer)
  File "/Users/Damon/python/lib/matplotlib/artist.py", line 55, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/Users/Damon/python/lib/matplotlib/figure.py", line 798, in draw
    func(*args)
  File "/Users/Damon/python/lib/matplotlib/artist.py", line 55, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/Users/Damon/python/lib/matplotlib/axes.py", line 1934, in draw
    a.draw(renderer)
  File "/Users/Damon/python/lib/matplotlib/artist.py", line 55, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/Users/Damon/python/lib/matplotlib/axis.py", line 1032, in draw
    self.label.draw(renderer)
  File "/Users/Damon/python/lib/matplotlib/artist.py", line 55, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/Users/Damon/python/lib/matplotlib/text.py", line 524, in draw
    bbox, info = self._get_layout(renderer)
  File "/Users/Damon/python/lib/matplotlib/text.py", line 307, in _get_layout
    ismath=ismath)
  File "/Users/Damon/python/lib/matplotlib/backends/backend_pdf.py", line 1766, in get_text_width_height_descent
    renderer=self)
  File "/Users/Damon/python/lib/matplotlib/texmanager.py", line 606, in get_text_width_height_descent
    dvifile = self.make_dvi(tex, fontsize)
  File "/Users/Damon/python/lib/matplotlib/texmanager.py", line 371, in make_dvi
    string:\n%s\nHere is the full report generated by LaTeX: \n\n'% repr(tex)) + report)
RuntimeError: LaTeX was not able to process the following string:
'$\\mathbb{TEST}$'
Here is the full report generated by LaTeX: 

This is pdfTeXk, Version 3.1415926-1.40.9 (Web2C 7.5.7)
 %&-line parsing enabled.
entering extended mode
(./050cefddb6041784b9620f96ff8c63bd.tex
LaTeX2e <2005/12/01>
Babel <v3.8l> and hyphenation patterns for english, usenglishmax, dumylang, noh
yphenation, german-x-2008-06-18, ngerman-x-2008-06-18, ancientgreek, ibycus, ar
abic, basque, bulgarian, catalan, pinyin, coptic, croatian, czech, danish, dutc
h, esperanto, estonian, farsi, finnish, french, galician, german, ngerman, mono
greek, greek, hungarian, icelandic, indonesian, interlingua, irish, italian, la
tin, mongolian, mongolian2a, bokmal, nynorsk, polish, portuguese, romanian, rus
sian, sanskrit, serbian, slovak, slovenian, spanish, swedish, turkish, ukenglis
h, ukrainian, uppersorbian, welsh, loaded.
(/usr/local/texlive/2008/texmf-dist/tex/latex/base/article.cls
Document Class: article 2005/09/16 v1.4f Standard LaTeX document class
(/usr/local/texlive/2008/texmf-dist/tex/latex/base/size10.clo))
(/usr/local/texlive/2008/texmf-dist/tex/latex/type1cm/type1cm.sty)
(/usr/local/texlive/2008/texmf-dist/tex/latex/psnfss/helvet.sty
(/usr/local/texlive/2008/texmf-dist/tex/latex/graphics/keyval.sty))
(/usr/local/texlive/2008/texmf-dist/tex/latex/psnfss/courier.sty)
(/usr/local/texlive/2008/texmf-dist/tex/latex/base/textcomp.sty
(/usr/local/texlive/2008/texmf-dist/tex/latex/base/ts1enc.def))
(/usr/local/texlive/2008/texmf-dist/tex/latex/geometry/geometry.sty
(/usr/local/texlive/2008/texmf-dist/tex/xelatex/xetexconfig/geometry.cfg)

Package geometry Warning: Over-specification in `h'-direction.
    `width' (5058.9pt) is ignored.


Package geometry Warning: Over-specification in `v'-direction.
    `height' (5058.9pt) is ignored.

)
No file 050cefddb6041784b9620f96ff8c63bd.aux.
(/usr/local/texlive/2008/texmf-dist/tex/latex/base/ts1cmr.fd)
! Undefined control sequence.
<recently read> \mathbb 
                        
l.12 ...e{12.000000}{15.000000}{\rmfamily $\mathbb
                                                  {TEST}$}
[1] (./050cefddb6041784b9620f96ff8c63bd.aux) )
(see the transcript file for additional information)
Output written on 050cefddb6041784b9620f96ff8c63bd.dvi (1 page, 220 bytes).
Transcript written on 050cefddb6041784b9620f96ff8c63bd.log.