Fix Issue14721: Send Content-length: 0 for empty body () in the http.request
diff --git a/Lib/httplib.py b/Lib/httplib.py
index 5d16e53..98296dc 100644
--- a/Lib/httplib.py
+++ b/Lib/httplib.py
@@ -989,7 +989,7 @@
 
         self.putrequest(method, url, **skips)
 
-        if body and ('content-length' not in header_names):
+        if body is not None and 'content-length' not in header_names:
             self._set_content_length(body)
         for hdr, value in headers.iteritems():
             self.putheader(hdr, value)