<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _advertisement(self):
 """Create advertisement data."""

        # Flags are
        # bit 0: whether we have pending data
        # bit 1: whether we are in a low voltage state
        # bit 2: whether another user is connected
        # bit 3: whether we support robust reports
        # bit 4: whether we allow fast writes

        flags = int(self.device.pending_data) | (0 << 1) | (0 << 2) | (1 << 3) | (1 << 4)
        return struct.pack("<LH", self.device.iotile_id, flags)