How to call a Function Module within Function module for Generic Extractor

I have a Scenario where I have to call a Function Module within Function module for Generic Extractor based on FM.

I have already copied the FM “ZRSAX_BIW_GET_DATA_SIMPLE_TEST” from the RSAX function group.

Now in my Scenario I need create a Generic extractor based on FM and I need to call the FM “SBIC_CURRENCIES_TRANSFER” in the “ZRSAX_BIW_GET_DATA_SIMPLE_TEST”.

Could you please let me know, how I can achieve this.

Thanks in Advance