title: How to get protocol numbers in PCAP file?
body: <p>Some protocols numbers are:</p>
  
  <p>6     TCP     Transmission Control        [RFC793]
   ...
  17    UDP     User Datagram               [RFC768]   </p>
  
  <p>by IANA.</p>
  
  <pre><code>import pyshark
  
  pkts = pyshark.FileCapture('testes.pcap')
  </code></pre>
  
  <p>I just want to print all protocols number in PCAP file and save then in a file. How can I get it using pyshark?</p>