#!/bin/bash
sed -e 's/{\(\([0-9.]\+\|false\|true\|null\|"[^"]*"\) *,\)/[\1/g' \
 -e 's/\(, *\([0-9.]\+\|false\|true\|null\|"[^"]*"\)\)}/\1]/g'

IyEvYmluL2Jhc2gKc2VkIC1lICdzL3tcKFwoWzAtOS5dXCtcfGZhbHNlXHx0cnVlXHxudWxsXHwiW14iXSoiXCkgKixcKS9bXDEvZycgXAogICAgLWUgJ3MvXCgsICpcKFswLTkuXVwrXHxmYWxzZVx8dHJ1ZVx8bnVsbFx8IlteIl0qIlwpXCl9L1wxXS9nJw==

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

{"hello": 1, "grid": {"C1", "D1", "E1", "C2", "D2", "E2", "F2", "B3", "C3", "D3", "E3", "F3", "B4", "C4", "D4", "E4", "F4", "C5", "D5", "E5", "F5", "C6", "D6", "E6"}, "something": "else"}