AttributeError: 'module' object has no attribute 'packet_encoder'

[Yash-dev1]

When I try to run the encdec_custom_fec.grc example, I get the following error:
Generating: '/home/dragon/gr-packetizer/examples/encdec_custom_fec.py
Executing: /usr/bin/python -u /home/dragon/gr-packetizer/examples/encdec_custom_fec.py
Using Volk machine: avx2_64_mmx_orc Traceback (most recent call last): File "/home/dragon/gr-packetizer/examples/encdec_custom_fec.py", line 432, in <module>
main() File "/home/dragon/gr-packetizer/examples/encdec_custom_fec.py", line 420, in main tb = top_block_cls(frame_size=options.frame_size, puncpat=options.puncpat) File "/home/dragon/gr-packetizer/examples/encdec_custom_fec.py", line 240, in __init__
self.packetizer_packet_encoder_0 = packetizer.packet_encoder((preamble), constel_header.base(), constel_payload.base(), header_formatter.base(), False, False, "packet_len", 0, False, 1)
AttributeError: 'module' object has no attribute 'packet_encoder'
I'm using GNU Radio Companion 3.7.9 on Ubuntu 16.04. I dont know how to resolve this issue.Any leads will be thankful

[josephjosuuu]

Have you installed the gr-packetizer module?