Update library/itertools.po

Co-authored-by: Dr.XYZ <[email protected]>

Author: hsiangjenli

library/itertools.po

@@ -1992,7 +1992,7 @@ msgstr ""
 "    return list(islice(iterable, n))\n"
 "\n"
 "def prepend(value, iterable):\n"
-"    \"在可疊代物件前插入單一值。\"\n"
+"    \"在可疊代物件開頭插入單一值。\"\n"
 "    # prepend(1, [2, 3, 4]) → 1 2 3 4\n"
 "    return chain([value], iterable)\n"
 "\n"