instruction: Write Docker code for networking
output: ```bash
  # ping -c 2 google.com
  
  PING google.com (172.217.3.174): 56 data bytes
  64 bytes from 172.217.3.174: seq=0 ttl=41 time=9.778 ms
  64 bytes from 172.217.3.174: seq=1 ttl=41 time=9.634 ms
  
  --- google.com ping statistics ---
  2 packets transmitted, 2 packets received, 0% packet loss
  round-trip min/avg/max = 9.634/9.706/9.778 ms
  
  CTRL+p CTRL+q
  
  $ docker container attach alpine3
  
  # ping -c 2 google.com
  
  PING google.com (172.217.3.174): 56 data bytes
  64 bytes from 172.217.3.174: seq=0 ttl=41 time=9.706 ms
  64 bytes from 172.217.3.174: seq=1 ttl=41 time=9.851 ms
  
  --- google.com ping statistics ---
  2 packets transmitted, 2 packets received, 0% packet loss
  round-trip min/avg/max = 9.706/9.778/9.851 ms
  
  CTRL+p CTRL+q
  
  $ docker container attach alpine1
  
  # ping -c 2 google.com
  
  PING google.com (172.217.3.174): 56 data bytes
  64 bytes from 172.217.3.174: seq=0 ttl=41 time=9.606 ms
  64 bytes from 172.217.3.174: seq=1 ttl=41 time=9.603 ms
  
  --- google.com ping statistics ---
  2 packets transmitted, 2 packets received, 0% packet loss
  round-trip min/avg/max = 9.603/9.604/9.606 ms
  
  CTRL+p CTRL+q
  ```