shithub: kwa

ref: 2af227c88bbcf8d6c52eb5b3b3a677d88a281774
dir: /test/p.35/

BEGIN			{ FS = OFS = "\t" }
$4 ~ /^North America$/	{ $4 = "NA" }
$4 ~ /^South America$/	{ $4 = "SA" }
			{ print }