code: public PropertyDocument copy(PropertyDocument object) {
  		return dataObjectFactory.getPropertyDocument(
  				copy(object.getEntityId()),
  				copyMonoLingualTextValues(object.getLabels().values()),
  				copyMonoLingualTextValues(object.getDescriptions().values()),
  				copyAliasMap(object.getAliases()),
  				copyStatementGroups(object.getStatementGroups()),
  				copy(object.getDatatype()),
  				object.getRevisionId());
  	}
docs: Copies a {@link PropertyDocument}.
  
  @param object
  object to copy
  @return copied object