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'use strict';
module.exports = function each(arr, cb, done) {  if (arr.length === 0) {    return done();  }
  let remaining = arr.length;  let err = null;  for (const v of arr) {    cb(v, function(_err) {      if (err != null) {        return;      }      if (_err != null) {        err = _err;        return done(err);      }
      if (--remaining <= 0) {        return done();      }    });  }};