C:\Users\buildbot\pypy_stuff\cffi>python demo\extern_python.py
_extern_python_cffi.c
   Creating library .\Release\_extern_python_cffi.lib and object .\Release\_extern_python_cffi.exp
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
extern "Python": function f() called, but no code was attached to it yet with @ffi.def_extern().  Returning 0.
Traceback (most recent call last):
  File "demo\extern_python.py", line 26, in <module>
    assert lib.my_algo(10) == 0+1+4+9+16+25+36+49+64+81
AssertionError

C:\Users\buildbot\pypy_stuff\cffi>python
Python 2.7.9 (default, Dec 10 2014, 12:24:55) [MSC v.1500 32 bit (Intel)] on win32
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