code: def p_include_once_ok(p):
      
      global CURRENT_DIR
      p[0] = [p[1] + p[2]] + p[3] + [p[4]]
      CURRENT_FILE.pop()  # Remove top of the stack
      CURRENT_DIR = os.path.dirname(CURRENT_FILE[-1])
docs: include_file : include_once NEWLINE program _ENDFILE_