TEST_IO_GRIB2 
-|-EXT_GR1_IOINIT 
-|-EXT_GR1_IOEXIT 
-|-EXT_GR1_OPEN_FOR_WRITE_BEGIN 
-|--|-GR1_GET_NEW_HANDLE 
-|-EXT_GR1_OPEN_FOR_WRITE_COMMIT 
-|-EXT_GR1_INQUIRE_OPENED 
-|-EXT_GR1_WRITE_FIELD 
-|--|-EXT_GR1_IOCLOSE 
-|--|-GET_DIMS 
-|--|-GET_VERT_STAG 
-|--|-GR1_GET_LEVELS 
-|--|-GETH_IDTS 
-|--|--|-NFEB 2
-|--|--|-NDFEB 2
-|-EXT_GR1_IOCLOSE