diff --git a/_sqlmap.py b/_sqlmap.py
index 7d6e97cc9..56b30e3a7 100755
--- a/_sqlmap.py
+++ b/_sqlmap.py
@@ -107,12 +107,12 @@ def main():
         kb.threadContinue = False
         kb.threadException = True
 
-        if conf.get("hashDB", None):
+        if conf.get("hashDB"):
             try:
                 conf.hashDB.flush(True)
             except KeyboardInterrupt:
                 pass
 
         # Reference: http://stackoverflow.com/questions/1635080/terminate-a-multi-thread-python-program
-        if conf.get("threads", 0) > 1 or conf.get("dnsServer", None):
+        if conf.get("threads", 0) > 1 or conf.get("dnsServer"):
             os._exit(0)
diff --git a/lib/core/threads.py b/lib/core/threads.py
index 9471c83e3..e5b449d00 100644
--- a/lib/core/threads.py
+++ b/lib/core/threads.py
@@ -195,7 +195,7 @@ def runThreads(numThreads, threadFunction, cleanupFunction=None, forwardExceptio
             if lock.locked_lock():
                 lock.release()
 
-        if conf.get("hashDB", None):
+        if conf.get("hashDB"):
             conf.hashDB.flush(True)
 
         if cleanupFunction:
diff --git a/lib/utils/hashdb.py b/lib/utils/hashdb.py
index a2ae4cda4..90ea5b633 100644
--- a/lib/utils/hashdb.py
+++ b/lib/utils/hashdb.py
@@ -57,7 +57,7 @@ class HashDB(object):
         retVal = None
         if key and (self._write_cache or os.path.isfile(self.filepath)):
             hash_ = HashDB.hashKey(key)
-            retVal = self._write_cache.get(hash_, None)
+            retVal = self._write_cache.get(hash_)
             if not retVal:
                 while True:
                     try: