$Batch read using Function Imports - Odata

Dear Experts,

I can able to perform multi read using $Batch.

For Ex :  SurveyEmpSet - Entity Set Name

GET SurveyEmpSet(EmpId='12345',EmpName='Test Emp1') HTTP/1.1

GET SurveyEmpSet(EmpId='45678',EmpName='Test Emp2') HTTP/1.1

But now I need the same for the function import to get output. What's the change I need to do in the above.

For Ex:  ContList is the Function Import Name.

/sap/opu/odata/sap/ZTEST_SRV/ContList?Lang='E'

/sap/opu/odata/sap/ZTEST_SRV/ContList?Lang='A'

Regards,

Srinivasan K