[Chepy](https://github.com/securisec/chepy)

```
from chepy import Chepy

c = Chepy("loopback.pcap")

flag = (
# read pcap
c.read_pcap()
# extract all ICMP payloads
.pcap_payload("ICMP")
# Because payloads repeat, extract only one
.select_every_n(2)
# pull the 16th byte of each payload which also repeats
.loop_list("slice", {"start": 16, "end": 17})
# join payload to form PNG file
.join_list(b"")
# extract binary strings
.extract_strings()
# extract flag
.search_ctf_flags(prefix="LLS")
)
print(flag)
```