code: function(sPropertyName) {
  			var oProperty = this._oPropertySet[sPropertyName];
  			if (oProperty == null) {
  				throw "no such property with name " + sPropertyName;
  			}
  
  			if (oProperty.extensions != undefined) {
  				for (var i = -1, oExtension; (oExtension = oProperty.extensions[++i]) !== undefined;) {
  					if (!oExtension.namespace == odata4analytics.constants.SAP_NAMESPACE) {
  						continue;
  					}
  					if (oExtension.name == "label") {
  						return oExtension.value;
  					}
  				}
  			}
  			return null;
  		}
docs: Get label of the property with specified name (identified by property
  metadata annotation sap:label)
  
  @param {string}
  sPropertyName Property name
  @returns {string} The label string
  @public
  @function
  @name sap.ui.model.analytics.odata4analytics.EntityType#getLabelOfProperty