TIBCO Spotfire

Hi , Am getting the below error if i write the below script and click run script .

 "type "is the property control  which i created . I am new to spotfire scripting ... could any one help why am getting this error ? Do i need to write any import statements at the begining of the script ? I have tried writing like that also but no luck ..

System.ArgumentException: The property 'type' does not exist in the DataPropertyRegistry.
   at Spotfire.Dxp.Data.DataPropertyRegistry.ValidateSetProperty(DataPropertyClass dataPropertyClass, String name, Object value)
   at Spotfire.Dxp.Data.DataProperties.DataPropertyContainer`1.SetProperty(String name, Object value)
   at Spotfire.Dxp.Data.DataColumnImpl.Spotfire.Dxp.Data.Collections.IDataPropertyContainer.SetProperty(String name, Object value)
   at Spotfire.Dxp.Data.DataColumn.Spotfire.Dxp.Data.Collections.IDataPropertyContainer.SetProperty(String name, Object value)
   at Spotfire.Dxp.Data.DataColumnProperties.SetProperty(String name, Object value)
   at _stub_$12##12(Closure , CallSite , CodeContext , Object , String , Object )
   at Microsoft.Scripting.Actions.MatchCaller.Call4[T0,T1,T2,T3,TRet](Func`6 target, CallSite site, Object[ args)
   at Microsoft.Scripting.Actions.CallSite`1.UpdateAndExecute(Object[ args)
   at Microsoft.Scripting.Actions.UpdateDelegates.Update4[T,T0,T1,T2,T3,TRet](CallSite site, T0 arg0, T1 arg1, T2 arg2, T3 arg3)
   at <module>$4##4(Closure , Scope , LanguageContext )
   at Microsoft.Scripting.Runtime.OptimizedScriptCode.InvokeTarget(LambdaExpression code, Scope scope)
   at Microsoft.Scripting.SourceUnit.Execute(Scope scope, ErrorSink errorSink)
   at Microsoft.Scripting.Hosting.ScriptSource.Execute(ScriptScope scope)
   at Spotfire.Dxp.Application.ScriptSupport.IronPythonScriptEngine.ExecuteForDebugging(String scriptCode, Dictionary`2 scope, Stream outputStream)
   at Spotfire.Dxp.Application.Scripting.ScriptService.ExecuteForDebugging(String scriptCode, Dictionary`2 scope, Stream outputStream)
   at Spotfire.Dxp.Application.Scripting.ScriptManager.<>c__DisplayClassd.<ExecuteScriptForDebugging>b__c()
   at Spotfire.Dxp.Framework.Commands.CommandHistory.Transaction(String displayName, Executor executor, Boolean visible, Boolean sticky, Guid stickyGuid)
   at Spotfire.Dxp.Framework.Commands.CommandHistory.Transaction(String displayName, Executor executor)
   at Spotfire.Dxp.Framework.DocumentModel.DocumentNode.Transaction(String displayName, Executor executor)
   at Spotfire.Dxp.Framework.DocumentModel.DocumentNode.Spotfire.Dxp.Framework.DocumentModel.ITransactions.ExecuteTransaction(Executor executor)
   at Spotfire.Dxp.Application.Scripting.ScriptManager.ExecuteScriptForDebugging(String scriptCode, Dictionary`2 scriptArguments, String& output)
   at Spotfire.Dxp.Forms.Framework.Scripting.ScriptEditDialog.RunButton_Click(Object sender, EventArgs e)