Ex_me_process_req_cust~process_header: How to Get Acct Assignment Data

Question

I've created a custom class to use this BADI interface. Inside this process_header method I get the Purchase Requisition's item data, I now need to read the Purchase Requisition's account data, particularly the GL Account Number, and then change it. See below. Any feedback will help.
  Thank-You.
METHOD IF_EX_ME_PROCESS_REQ_CUST~PROCESS_HEADER.
  DATA: LT_ITEMS TYPE MMPUR_REQUISITION_ITEMS.
  DATA: LS_ITEM TYPE MEREQ_ITEM.
  FIELD-SYMBOLS: <FS_ITEM> TYPE LINE OF MMPUR_REQUISITION_ITEMS.
  CALL METHOD IM_HEADER->GET_ITEMS
    RECEIVING
      RE_ITEMS = LT_ITEMS.
  LOOP AT LT_ITEMS ASSIGNING <FS_ITEM>.
    LS_ITEM = <FS_ITEM>-ITEM->GET_DATA( ).
  ENDLOOP.
*Get/Read the Purchase Requisition Line Item Account Assignment Data Here
*Change the Purchase Requisition Line Item GL Account (SET?)
ENDMETHOD.

Answer 1

The line that is commented out gets a syntax error...expecting a field or function? Is it looking for an interface name to be called out subsequent to get_exkn? I guess I can then do set_exkn once this compiles  Thank-You.
METHOD IF_EX_ME_PROCESS_REQ_CUST~PROCESS_HEADER.
  DATA: LT_ITEMS TYPE MMPUR_REQUISITION_ITEMS.
  DATA: LS_ITEM TYPE MEREQ_ITEM.
  DATA: LT_ACCT TYPE MMPUR_ACCOUNTING_LIST.
  DATA: LS_ACCT TYPE MMPUR_ACCOUNTING_LIST.
  FIELD-SYMBOLS: <FS_ITEM> TYPE LINE OF MMPUR_REQUISITION_ITEMS.
  FIELD-SYMBOLS: <FS_ACCT> TYPE LINE OF MMPUR_ACCOUNTING_LIST.
  CALL METHOD IM_HEADER->GET_ITEMS
    RECEIVING
      RE_ITEMS = LT_ITEMS.
  LOOP AT LT_ITEMS ASSIGNING <FS_ITEM>.
    LS_ITEM = <FS_ITEM>-ITEM->GET_DATA( ).
    LT_ACCT = <FS_ITEM>-ITEM->IF_ACCT_CONTAINER_MM~GET_ITEMS( ).
    LOOP AT LT_ACCT  ASSIGNING <FS_ACCT>.
*      LS_ACT =  <FS_ACCT>->GET_exkn( ).
    ENDLOOP.
  ENDLOOP.
ENDMETHOD.
Edited by: Tom Matys on Dec 6, 2011 9:22 PM