[Discuss-gnuradio] how does Packet Header Generator module handle tags

[Tiankun Hu]

Hi Experts,
I was reading tx_ofdm.py. I found this module use  'set_tag_propagation_policy(TPP_DONT)' to handle tags by itself, but I cann't find the code that used to handle tag in this module.
I knew this module will call 'packet_header_ofdm.header_formatter()' and 'packet_header_default.header_formatter()', but I also cann't find the handle tag code in these functions.
Anyone can help me figure out where does this module process tags?

Thanks
Tiankun