The manual refers to shell scripts. ie, DOS batch file uses %1 %2 etc. Unix uses $1 $2 etc. Python uses a function to retrieve the variable.
Python SABnzbd
sys.argv[1] 1-The final directory of the job (full path)
sys.argv[2] 2-The name of the NZB file
sys.argv[3] 3-Clean version of the job name (no path info and ".nzb" removed)
sys.argv[4] 4-Newzbin report number (may be empty
sys.argv[5] 5-Newzbin or user-defined category
sys.argv[6] 6-Group that the NZB was posted in e.g. alt.binaries.x
Python Example - Get final folder name from SAB
Python Example - Get clean NZB job name from SAB
Hope this helps.