code: function unwrap(attrVal) {
    var result = {};
    for (var key in attrVal) {
      if(attrVal.hasOwnProperty(key)) {
        var value = attrVal[key];
        if (value !== null && typeof value !== 'undefined') 
          result[key] = unwrap1(attrVal[key]);
      }
    }
    return result;
  }
docs: Unwrap DynamoDB AttributeValues to values of the appropriate types.
  @param {Object} attributeValue The DynamoDb AttributeValue to unwrap.
  @return {Object} Unwrapped object with properties.