our requirement is to export a file with plain text with header.

we are using D_pxNewFile file is creating but data is in base 64 format using pyContents, when using pyStream getting an error  as

Java Exception:    java.lang.ClassCastException: java.lang.String cannot be cast to java.io.InputStream 

and how to create header for the file.

Any suggestions or inputs, please let me know. Thanks in advance.