mongo Failed: invalid JSON input. Position code example

Example: mongoimport Failed: invalid JSON input. Position: 74. Character: I

you can use --legacy option of mongoimport in order to import the file
with the format you want with ObjectId("an oid"), NumberInt(an int) or
new Date("an iso date" or any mongo extension available in
extended json v1 : https://docs.mongodb.com/manual/reference/mongodb-extended-json-v1/)