This module defines a class which implements the client side of the
HTTP protocol. It is normally not used directly -- the module
urllib uses it to handle URLs that
use HTTP.
An HTTP instance
represents one transaction with an HTTP server. It should be
instantiated passing it a host and optional port number. If no port
number is passed, the port is extracted from the host string if it has
the form host:port, else the default HTTP port (80)
is used. If no host is passed, no connection is made, and the
connect() method should be used to connect to a server. For
example, the following calls all create instances that connect to the
server at the same host and port: