code: function(obj) {
      if (typeof obj !== 'object') {
        throw new Error('Argument must be an object');
      }
  
      Object.keys(obj).forEach(function(key) {
        if (obj[key] === null || obj[key] === undefined) {
          delete obj[key];
        }
      });
  
      return obj;
    }
docs: Remove empty values from an object