issue3972: HTTPConnection and HTTPSConnection now support a
source_address parameter.

Also cleans up an annotation in the socket documentation.
diff --git a/Lib/httplib.py b/Lib/httplib.py
index 39acd1c..c5e600c 100644
--- a/Lib/httplib.py
+++ b/Lib/httplib.py
@@ -658,8 +658,9 @@
     strict = 0
 
     def __init__(self, host, port=None, strict=None,
-                 timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+                 timeout=socket._GLOBAL_DEFAULT_TIMEOUT, source_address=None):
         self.timeout = timeout
+        self.source_address = source_address
         self.sock = None
         self._buffer = []
         self.__response = None
@@ -728,7 +729,7 @@
     def connect(self):
         """Connect to the host and port specified in __init__."""
         self.sock = socket.create_connection((self.host,self.port),
-                                             self.timeout)
+                                             self.timeout, self.source_address)
 
         if self._tunnel_host:
             self._tunnel()
@@ -1133,15 +1134,18 @@
         default_port = HTTPS_PORT
 
         def __init__(self, host, port=None, key_file=None, cert_file=None,
-                     strict=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
-            HTTPConnection.__init__(self, host, port, strict, timeout)
+                     strict=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
+                     source_address=None):
+            HTTPConnection.__init__(self, host, port, strict, timeout,
+                                    source_address)
             self.key_file = key_file
             self.cert_file = cert_file
 
         def connect(self):
             "Connect to a host on a given (SSL) port."
 
-            sock = socket.create_connection((self.host, self.port), self.timeout)
+            sock = socket.create_connection((self.host, self.port),
+                                            self.timeout, self.source_address)
             if self._tunnel_host:
                 self.sock = sock
                 self._tunnel()
diff --git a/Lib/test/test_httplib.py b/Lib/test/test_httplib.py
index cd54323..c0c12e7 100644
--- a/Lib/test/test_httplib.py
+++ b/Lib/test/test_httplib.py
@@ -3,7 +3,8 @@
 import StringIO
 import socket
 
-from unittest import TestCase
+import unittest
+TestCase = unittest.TestCase
 
 from test import test_support
 
@@ -237,6 +238,38 @@
     def test_responses(self):
         self.assertEquals(httplib.responses[httplib.NOT_FOUND], "Not Found")
 
+
+class SourceAddressTest(TestCase):
+    def setUp(self):
+        self.serv = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.port = test_support.bind_port(self.serv)
+        self.source_port = test_support.find_unused_port()
+        self.serv.listen(5)
+        self.conn = None
+
+    def tearDown(self):
+        if self.conn:
+            self.conn.close()
+            self.conn = None
+        self.serv.close()
+        self.serv = None
+
+    def testHTTPConnectionSourceAddress(self):
+        self.conn = httplib.HTTPConnection(HOST, self.port,
+                source_address=('', self.source_port))
+        self.conn.connect()
+        self.assertEqual(self.conn.sock.getsockname()[1], self.source_port)
+
+    @unittest.skipIf(not hasattr(httplib, 'HTTPSConnection'),
+                     'httplib.HTTPSConnection not defined')
+    def testHTTPSConnectionSourceAddress(self):
+        self.conn = httplib.HTTPSConnection(HOST, self.port,
+                source_address=('', self.source_port))
+        # We don't test anything here other the constructor not barfing as
+        # this code doesn't deal with setting up an active running SSL server
+        # for an ssl_wrapped connect() to actually return from.
+
+
 class TimeoutTest(TestCase):
     PORT = None
 
@@ -294,7 +327,7 @@
 
 def test_main(verbose=None):
     test_support.run_unittest(HeaderTests, OfflineTest, BasicTest, TimeoutTest,
-                              HTTPSTimeoutTest)
+                              HTTPSTimeoutTest, SourceAddressTest)
 
 if __name__ == '__main__':
     test_main()