Chapter 2 example style fix

Author: Artiom N.

src/book01/ch02/python/ip-convert.py

@@ -3,8 +3,8 @@
 import socket
 
 
-ip4 = socket.inet_pton(socket.AF_INET, "10.12.110.57")
-ip6 = socket.inet_pton(socket.AF_INET6, "2001:db8:63b3:1::3490")
+ip4 = socket.inet_pton(socket.AF_INET, '10.12.110.57')
+ip6 = socket.inet_pton(socket.AF_INET6, '2001:db8:63b3:1::3490')
 
 print(socket.inet_ntop(socket.AF_INET, ip4))
 print(socket.inet_ntop(socket.AF_INET6, ip6))