>>> import pfromf
>>> pfromf.f2()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
pfromf.error: Callback fpy not defined (as an argument or module pfromf attribute).

>>> def f(): print("python f")
... 
>>> pfromf.fpy = f
>>> pfromf.f2()
 in f2, calling f2py..
python f
>>> pfromf.f1()
 in f1, calling f2 twice..
 in f2, calling f2py..
python f
 in f2, calling f2py..
python f
>>> 