Yep:

``` python
>>> ax = plt.axes(xticks=[])
>>> sizes = [tick.get_fontsize() for tick in ax.xaxis.get_ticklabels()]
>>> if sizes[1:] == sizes[:-1]:
        print sizes[0]
---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-7-1aaa37478b98> in <module>()
      1 if sizes[1:] == sizes[:-1]:
----> 2     print sizes[0]
      3 

IndexError: list index out of range
```