LIST
 FUNCTION
  IDENTIFIER (main)
  LIST
  BLOCK
   LIST
    PRINT_STATEMENT
     LIST
      STRING_LITERAL ("Should be 7:")
      FUNCTION_CALL
       IDENTIFIER (identity)
       LIST
        FUNCTION_CALL
         IDENTIFIER (first)
         LIST
          FUNCTION_CALL
           IDENTIFIER (second)
           LIST
            NUMBER_LITERAL (5)
            NUMBER_LITERAL (7)
          FUNCTION_CALL
           IDENTIFIER (first)
           LIST
            NUMBER_LITERAL (2)
            NUMBER_LITERAL (9)
 FUNCTION
  IDENTIFIER (identity)
  LIST
   IDENTIFIER (argument)
  BLOCK
   LIST
    RETURN_STATEMENT
     IDENTIFIER (argument)
 FUNCTION
  IDENTIFIER (first)
  LIST
   IDENTIFIER (a)
   IDENTIFIER (b)
  BLOCK
   LIST
    RETURN_STATEMENT
     IDENTIFIER (a)
 FUNCTION
  IDENTIFIER (second)
  LIST
   IDENTIFIER (a)
   IDENTIFIER (b)
  BLOCK
   LIST
    RETURN_STATEMENT
     IDENTIFIER (b)