Doctest failure

File "/home/scolobb/Dropbox/prj/sympy/sympy/core/compatibility.py", line 17, in sympy.core.compatibility.SymPyDeprecationWarning
Failed example:
    warnings.warn("Don't do this, it's deprecated", SymPyDeprecationWarning)
Expected:
    __main__:1: SymPyDeprecationWarning: "Don't do this, it's deprecated"
Got nothing