primaryRegion
 The Amazon Web Services Region of the new primary key. Enter the Region ID, such as us-east-1 or
 ap-southeast-2. There must be an existing replica key in this Region.
 
When the operation completes, the multi-Region key in this Region will be the primary key.
- Parameters:
- primaryRegion- The Amazon Web Services Region of the new primary key. Enter the Region ID, such as- us-east-1or- ap-southeast-2. There must be an existing replica key in this Region.- When the operation completes, the multi-Region key in this Region will be the primary key. 
- Returns:
- Returns a reference to this object so that method calls can be chained together.