The string used for indention.
When generating multi-line output, this string is inserted once at the beginning of each indented line for each level of indentation.
If null, the output is encoded as a single line.
final String indent
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Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dartlang.org/stable/2.0.0/dart-convert/JsonEncoder/indent.html