static find(id, callback) {

    let db = this.prototype.db;

    // legacy support
    if (arguments.length === 3) {
      db = arguments[0];
      id = arguments[1];
      callback = arguments[2];
    }

    return new Composer(this)
      .where({id: id})
      .end((err, models) => {

        if (!err && !models.length) {
          let err = new Error(`Could not find ${this.name} with id "${id}".`);
          err.notFound = true;
          return callback(err);
        }

        callback(err, models[0]);

      });

  }
Finds a model with a provided id, otherwise returns a notFound error.
@param {number} id The id of the model you're looking for
@param {function({Error} err, {Nodal.Model} model)} callback The callback to execute upon completion