5th debugging example

Try

./make_module_1.sh gridloop5

and experience

python -c import ext_gridloop; print dir(ext_gridloop); \
           print ext_gridloop.__doc__
Traceback (most recent call last):
  File "<string>", line 1, in ?
ImportError: ./ext_gridloop.so: undefined symbol: mydebug

gridloop2 in gridloop5.c calls a function mydebug, but the function is not implemented (or linked)

Again, a precise ImportError helps detecting the problem