Calling ReportViewer.ServerReport.Render from IronPython

I'm trying to call ReportViewer.ServerReport.Render similar to what we did in VB.NET or C# this way,

exportBytes = ReportViewer1.ServerReport.Render("PDF",None,mimeType,encoding,fileNameExtension,streamids,
Warning) 

But I'm getting this error "expected 开发者_如何学CReference,but found null"

ServerReport is null, probably the report viewer is not properly initialized.