python - Having problems with **advance formatting method syntax**? -


what value 0 in front of [].

>>>somelist = list('spam')  >>>'first = {0[0]}, third = {0[2]}' .format(somelist)  'first=s, third=a'

0 represents first argument of format function, somelist.

this means 0 replaced somelist , first ([0]) , third ([2]) elements used in string.

therefore 0 ['s', 'p', 'a', 'm'], 0[0] 's' , 0[2] 'a'.


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