code: public PropertyDocument createPropertyDocument(
  			PropertyDocument propertyDocument, String summary)
  			throws IOException, MediaWikiApiErrorException {
  		String data = JsonSerializer.getJsonString(propertyDocument);
  		return (PropertyDocument) this.wbEditingAction
  				.wbEditEntity(null, null, null, "property", data, false,
  						this.editAsBot, 0, summary);
  	}
docs: Creates a new property document with the summary message as provided.
  <p>
  The property document that is given as a parameter must use a local
  property id, such as {@link PropertyIdValue#NULL}, and its revision id
  must be 0. The newly created document is returned. It will contain the
  new property id and revision id. Note that the site IRI used in the
  property id is not part of the API response; the site IRI given when
  constructing this object is used in this place.
  <p>
  Statements in the given data must have empty statement IDs.
  
  @param propertyDocument
  the document that contains the data to be written
  @param summary
  additional summary message for the edit, or null to omit this
  @return newly created property document, or null if there was an error
  @throws IOException
  if there was an IO problem, such as missing network
  connection
  @throws MediaWikiApiErrorException