python - what does : do when assigning flags in a command line argument? -


i trying add command line arguments program writing. found tutorial on-line i'm not entirely sure of lines do.the main bit don't understand : when assigning flags eg. "hi:o:"

why there 2 :'s around o? not h or i? also, have understood correctly first list "hi:o:" shorthand , second list ["ifile=","ofile="]is more verbose version? 

try:       opts, args = getopt.getopt(argv,"hi:o:",["ifile=","ofile="])    except getopt.getopterror:       print 'test.py -i <inputfile> -o <outputfile>'       sys.exit(2)

thanks!

the : indicates preceding option takes argument. is, call program -i inputfile -o outputfile.

your intuition second list correct.


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