diff --git a/src/horizon/listen.py b/src/horizon/listen.py
index 0b36bf0e..a8fbc4ae 100644
--- a/src/horizon/listen.py
+++ b/src/horizon/listen.py
@@ -2,7 +2,7 @@
 from os import kill, getpid
 from Queue import Full
 from multiprocessing import Process
-from struct import Struct, unpack
+from struct import Struct
 from msgpack import unpackb
 
 import logging
@@ -10,19 +10,19 @@
 
 logger = logging.getLogger("HorizonLog")
 
-##SafeUnpickler taken from Carbon: https://github.com/graphite-project/carbon/blob/master/lib/carbon/util.py
+# SafeUnpickler taken from Carbon: https://github.com/graphite-project/carbon/blob/master/lib/carbon/util.py
 import sys
 try:
-  from cStringIO import StringIO
+    from cStringIO import StringIO
 except ImportError:
-  from StringIO import StringIO
+    from StringIO import StringIO
 
 try:
-  import cPickle as pickle
-  USING_CPICKLE = True
+    import cPickle as pickle
+    USING_CPICKLE = True
 except:
-  import pickle
-  USING_CPICKLE = False
+    import pickle
+    USING_CPICKLE = False
 
 # This whole song & dance is due to pickle being insecure
 # yet performance critical for carbon. We leave the insecure
@@ -30,47 +30,49 @@
 # The SafeUnpickler classes were largely derived from
 # http://nadiana.com/python-pickle-insecure
 if USING_CPICKLE:
-  class SafeUnpickler(object):
-    PICKLE_SAFE = {
-      'copy_reg' : set(['_reconstructor']),
-      '__builtin__' : set(['object']),
-    }
+    class SafeUnpickler(object):
+        PICKLE_SAFE = {
+            'copy_reg': set(['_reconstructor']),
+            '__builtin__': set(['object']),
+        }
 
     @classmethod
     def find_class(cls, module, name):
-      if not module in cls.PICKLE_SAFE:
-        raise pickle.UnpicklingError('Attempting to unpickle unsafe module %s' % module)
-      __import__(module)
-      mod = sys.modules[module]
-      if not name in cls.PICKLE_SAFE[module]:
-        raise pickle.UnpicklingError('Attempting to unpickle unsafe class %s' % name)
-      return getattr(mod, name)
+        if module not in cls.PICKLE_SAFE:
+            raise pickle.UnpicklingError('Attempting to unpickle unsafe module %s' % module)
+        __import__(module)
+        mod = sys.modules[module]
+        if name not in cls.PICKLE_SAFE[module]:
+            raise pickle.UnpicklingError('Attempting to unpickle unsafe class %s' % name)
+        return getattr(mod, name)
 
     @classmethod
     def loads(cls, pickle_string):
-      pickle_obj = pickle.Unpickler(StringIO(pickle_string))
-      pickle_obj.find_global = cls.find_class
-      return pickle_obj.load()
+        pickle_obj = pickle.Unpickler(StringIO(pickle_string))
+        pickle_obj.find_global = cls.find_class
+        return pickle_obj.load()
 
 else:
-  class SafeUnpickler(pickle.Unpickler):
-    PICKLE_SAFE = {
-      'copy_reg' : set(['_reconstructor']),
-      '__builtin__' : set(['object']),
-    }
-    def find_class(self, module, name):
-      if not module in self.PICKLE_SAFE:
-        raise pickle.UnpicklingError('Attempting to unpickle unsafe module %s' % module)
-      __import__(module)
-      mod = sys.modules[module]
-      if not name in self.PICKLE_SAFE[module]:
-        raise pickle.UnpicklingError('Attempting to unpickle unsafe class %s' % name)
-      return getattr(mod, name)
+    class SafeUnpickler(pickle.Unpickler):
+        PICKLE_SAFE = {
+            'copy_reg': set(['_reconstructor']),
+            '__builtin__': set(['object']),
+        }
+
+        def find_class(self, module, name):
+            if module not in self.PICKLE_SAFE:
+                raise pickle.UnpicklingError('Attempting to unpickle unsafe module %s' % module)
+            __import__(module)
+            mod = sys.modules[module]
+            if name not in self.PICKLE_SAFE[module]:
+                raise pickle.UnpicklingError('Attempting to unpickle unsafe class %s' % name)
+            return getattr(mod, name)
 
     @classmethod
     def loads(cls, pickle_string):
-      return cls(StringIO(pickle_string)).load()
-##//SafeUnpickler
+        return cls(StringIO(pickle_string)).load()
+# //SafeUnpickler
+
 
 class Listen(Process):
     """
@@ -90,7 +92,7 @@ def __init__(self, port, queue, parent_pid, type="pickle"):
         self.current_pid = getpid()
         self.type = type
 
-        ##Use the safe unpickler that comes with carbon rather than standard python pickle/cpickle
+        # Use the safe unpickler that comes with carbon rather than standard python pickle/cpickle
         self.unpickler = SafeUnpickler
 
     def gen_unpickle(self, infile):