The source attribute name and an optional default value to use if a document doesn't have an attribute of that name.

 /// <summary>
 /// Sets the SourceDataCopy property
 /// </summary>
 /// <param name="sourceDataCopy">The value to set for the SourceDataCopy property </param>
 /// <returns>this instance</returns>
 public SourceAttribute WithSourceDataCopy(SourceData sourceDataCopy)
 {
     this.sourceDataCopy = sourceDataCopy;
     return(this);
 }
 /// <summary>
 /// Sets the SourceDataCopy property
 /// </summary>
 /// <param name="sourceDataCopy">The value to set for the SourceDataCopy property </param>
 /// <returns>this instance</returns>
 public SourceAttribute WithSourceDataCopy(SourceData sourceDataCopy)
 {
     this.sourceDataCopy = sourceDataCopy;
     return this;
 }