Attribute is not valid for ad type

Question

I have the following code, but I get the following compilation errors:

WebPartStorage attribute is not valid for this ad type. It is valid only for 'property, indexer' declarations.

and

FriendlyName is not valid for this ad type. It is valid only for 'property, indexer' declarations.

I changed my code from an MSDN article: http://msdn.microsoft.com/en-us/library/dd584174(office.11).aspx . Does anyone know what I'm doing wrong what causes this error?

  [Category("Custom Properties")]
    [DefaultValue(RegionEnum.None)]
    [WebPartStorage(Storage.Shared)]
    [FriendlyName("Region")]
    [Description("Select a value from the dropdown list.")]
    [Browsable(true)]
    protected RegionEnum _Region;
    public RegionEnum Region
    {
        get
        {
            return _Region;
        }
        set
        {
            _Region = value;
        }
    }

Answer 1

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; ( ); , : ?

protected RegionEnum _Region;
[Category("Custom Properties")]
[DefaultValue(RegionEnum.None)]
[WebPartStorage(Storage.Shared)]
[FriendlyName("Region")]
[Description("Select a value from the dropdown list.")]
[Browsable(true)]
public RegionEnum Region
{
    get { return _Region; }
    set { _Region = value; }
}

Answer 2

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protected RegionEnum _Region;

[Category("Custom Properties")]
[DefaultValue(RegionEnum.None)]
[Description("Select a value from the dropdown list.")]
[Browsable(true)]
[WebPartStorage(Storage.Shared)]
[FriendlyName("Region")]
public RegionEnum Region
{
    get
    {
        return _Region;
    }
    set
    {
        _Region = value;
    }
}

Answer 3

, using Microsoft.SharePoint.WebPartPages;, ?