Remove Python < 2.6 compatibility imports from testserver.py.

Split out of https://chromiumcodereview.appspot.com/10073033.

BUG=none
TBR=rsleevi@chromium.org

Review URL: https://codereview.chromium.org/10909251

git-svn-id: http://src.chromium.org/svn/trunk/src/net/tools/testserver@158196 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
diff --git a/testserver.py b/testserver.py
index ff684a8..aeb0575 100755
--- a/testserver.py
+++ b/testserver.py
@@ -18,7 +18,9 @@
 import BaseHTTPServer
 import cgi
 import errno
+import hashlib
 import httplib
+import json
 import minica
 import optparse
 import os
@@ -44,18 +46,6 @@
 import tlslite
 import tlslite.api
 
-try:
-  import hashlib
-  _new_md5 = hashlib.md5
-except ImportError:
-  import md5
-  _new_md5 = md5.new
-
-try:
-  import json
-except ImportError:
-  import simplejson as json
-
 if sys.platform == 'win32':
   import msvcrt
 
@@ -1318,7 +1308,7 @@
    """
    if force_reset or not self.server.nonce_time:
      self.server.nonce_time = time.time()
-   return _new_md5('privatekey%s%d' %
+   return hashlib.md5('privatekey%s%d' %
                    (self.path, self.server.nonce_time)).hexdigest()
 
   def AuthDigestHandler(self):
@@ -1333,7 +1323,7 @@
 
     stale = 'stale' in self.path
     nonce = self.GetNonce(force_reset=stale)
-    opaque = _new_md5('opaque').hexdigest()
+    opaque = hashlib.md5('opaque').hexdigest()
     password = 'secret'
     realm = 'testrealm'
 
@@ -1355,14 +1345,14 @@
 
       # Check the 'response' value and make sure it matches our magic hash.
       # See http://www.ietf.org/rfc/rfc2617.txt
-      hash_a1 = _new_md5(
+      hash_a1 = hashlib.md5(
           ':'.join([pairs['username'], realm, password])).hexdigest()
-      hash_a2 = _new_md5(':'.join([self.command, pairs['uri']])).hexdigest()
+      hash_a2 = hashlib.md5(':'.join([self.command, pairs['uri']])).hexdigest()
       if 'qop' in pairs and 'nc' in pairs and 'cnonce' in pairs:
-        response = _new_md5(':'.join([hash_a1, nonce, pairs['nc'],
+        response = hashlib.md5(':'.join([hash_a1, nonce, pairs['nc'],
             pairs['cnonce'], pairs['qop'], hash_a2])).hexdigest()
       else:
-        response = _new_md5(':'.join([hash_a1, nonce, hash_a2])).hexdigest()
+        response = hashlib.md5(':'.join([hash_a1, nonce, hash_a2])).hexdigest()
 
       if pairs['response'] != response:
         raise Exception('wrong password')