examples/http_client.py: Improve CPython compatibility in stream mode.

examples/network/http_client.py

 try:
-    import usocket as _socket
+    import usocket as socket
 except:
-    import _socket
+    import socket
 
 
-s = _socket.socket()
+s = socket.socket()
 
-ai = _socket.getaddrinfo("google.com", 80)
+ai = socket.getaddrinfo("google.com", 80)
 print("Address infos:", ai)
 addr = ai[0][4]
 
@@ -14,8 +14,10 @@ print("Connect address:", addr)
 s.connect(addr)
 
 if 0:
-    # MicroPython rawsocket module supports file interface directly
-    s.write("GET / HTTP/1.0\n\n")
+    # MicroPython socket objects support stream (aka file) interface
+    # directly, but the line below is needed for CPython.
+    s = s.makefile("rwb", 0)
+    s.write(b"GET / HTTP/1.0\n\n")
     print(s.readall())
 else:
     s.send(b"GET / HTTP/1.0\n\n")