MongoDB Drop Duplicate entries

drop.js

db.MyCollection.aggregate([
  {
    $group: {
      _id: "$col",
      duplicates: { $addToSet: "$_id" },
      count: { $sum: 1 },
    },
  },
  { $match: { count: { $gt: 1 } } },
])
  .toArray()
  .forEach(function (doc) {
    doc.duplicates.shift();
    db.MyCollection.remove({ _id: { $in: doc.duplicates } });
  });