diff --git a/flake8/mccabe.py b/flake8/mccabe.py
index b693ca7..ec5118b 100644
--- a/flake8/mccabe.py
+++ b/flake8/mccabe.py
@@ -3,7 +3,13 @@
     http://nedbatchelder.com/blog/200803/python_code_complexity_microtool.html
     MIT License.
 """
-import compiler
+try:
+    from compiler.visitor import ASTVisitor as Visitor
+    from compiler import parse
+except ImportError:
+    from ast import NodeVisitor as Visitor
+    from ast import parse
+
 import optparse
 import sys
 
@@ -14,8 +20,8 @@ class PathNode:
         self.look = look
 
     def to_dot(self):
-        print 'node [shape=%s,label="%s"] %d;' % \
-                (self.look, self.name, self.dot_id())
+        print('node [shape=%s,label="%s"] %d;' % \
+                (self.look, self.name, self.dot_id()))
 
     def dot_id(self):
         return id(self)
@@ -36,13 +42,13 @@ class PathGraph:
         self.nodes.setdefault(n1, []).append(n2)
 
     def to_dot(self):
-        print 'subgraph {'
+        print('subgraph {')
         for node in self.nodes:
             node.to_dot()
         for node, nexts in self.nodes.items():
             for next in nexts:
-                print '%s -- %s;' % (node.dot_id(), next.dot_id())
-        print '}'
+                print('%s -- %s;' % (node.dot_id(), next.dot_id()))
+        print('}')
 
     def complexity(self):
         """ Return the McCabe complexity for the graph.
@@ -53,13 +59,13 @@ class PathGraph:
         return num_edges - num_nodes + 2
 
 
-class PathGraphingAstVisitor(compiler.visitor.ASTVisitor):
+class PathGraphingAstVisitor(Visitor):
     """ A visitor for a parsed Abstract Syntax Tree which finds executable
         statements.
     """
 
     def __init__(self):
-        compiler.visitor.ASTVisitor.__init__(self)
+        Visitor.__init__(self)
         self.classname = ""
         self.graphs = {}
         self.reset()
@@ -175,9 +181,9 @@ class PathGraphingAstVisitor(compiler.visitor.ASTVisitor):
 def get_code_complexity(code, min=7, filename='stdin'):
     complex = []
     try:
-        ast = compiler.parse(code)
+        ast = parse(code)
     except AttributeError as e:
-        print >> sys.stderr, "Unable to parse %s: %s" % (filename, e)
+        sys.stderr.write("Unable to parse %s: %s\n" % (filename, e))
         return 0
 
     visitor = PathGraphingAstVisitor()
@@ -215,20 +221,20 @@ def main(argv):
     options, args = opar.parse_args(argv)
 
     text = open(args[0], "rU").read() + '\n\n'
-    ast = compiler.parse(text)
+    ast = parse(text)
     visitor = PathGraphingAstVisitor()
     visitor.preorder(ast, visitor)
 
     if options.dot:
-        print 'graph {'
+        print('graph {')
         for graph in visitor.graphs.values():
             if graph.complexity() >= options.min:
                 graph.to_dot()
-        print '}'
+        print('}')
     else:
         for graph in visitor.graphs.values():
             if graph.complexity() >= options.min:
-                print graph.name, graph.complexity()
+                print(graph.name, graph.complexity())
 
 
 if __name__ == '__main__':
diff --git a/flake8/pyflakes.py b/flake8/pyflakes.py
index 036b25c..00aa8fd 100644
--- a/flake8/pyflakes.py
+++ b/flake8/pyflakes.py
@@ -2,7 +2,11 @@
 # (c) 2005-2010 Divmod, Inc.
 # See LICENSE file for details
 
-import __builtin__
+try:
+    import __builtin__
+except ImportError:
+    import builtins as __builtin__
+
 import os.path
 import _ast
 import sys
@@ -251,7 +255,7 @@ class Checker(object):
                 all = []
 
             # Look for imported names that aren't used.
-            for importation in scope.itervalues():
+            for importation in scope.values():
                 if isinstance(importation, Importation):
                     if not importation.used and importation.name not in all:
                         self.report(
@@ -284,7 +288,7 @@ class Checker(object):
     def handleNode(self, node, parent):
         node.parent = parent
         if self.traceTree:
-            print '  ' * self.nodeDepth + node.__class__.__name__
+            print('  ' * self.nodeDepth + node.__class__.__name__)
         self.nodeDepth += 1
         if self.futuresAllowed and not \
                (isinstance(node, _ast.ImportFrom) or self.isDocstring(node)):
@@ -296,7 +300,7 @@ class Checker(object):
         finally:
             self.nodeDepth -= 1
         if self.traceTree:
-            print '  ' * self.nodeDepth + 'end ' + node.__class__.__name__
+            print ('  ' * self.nodeDepth + 'end ' + node.__class__.__name__)
 
     def ignore(self, node):
         pass
@@ -527,10 +531,15 @@ class Checker(object):
                     if isinstance(arg, _ast.Tuple):
                         addArgs(arg.elts)
                     else:
-                        if arg.id in args:
+                        try:
+                            id_ = arg.id
+                        except AttributeError:
+                            id_ = arg.arg
+
+                        if id_ in args:
                             self.report(messages.DuplicateArgument,
-                                        node.lineno, arg.id)
-                        args.append(arg.id)
+                                        node.lineno, id_)
+                        args.append(id_)
 
             self.pushFunctionScope()
             addArgs(node.args.args)
@@ -554,7 +563,7 @@ class Checker(object):
                 """
                 Check to see if any assignments have not been used.
                 """
-                for name, binding in self.scope.iteritems():
+                for name, binding in self.scope.items():
                     if (not binding.used and not name in self.scope.globals
                         and isinstance(binding, Assignment)):
                         self.report(messages.UnusedVariable,
@@ -629,8 +638,9 @@ def checkPath(filename):
     @return: the number of warnings printed
     """
     try:
-        return check(file(filename, 'U').read() + '\n', filename)
-    except IOError, msg:
+        return check(open(filename, 'U').read() + '\n', filename)
+    except IOError:
+        msg = sys.exc_info()[1]
         print >> sys.stderr, "%s: %s" % (filename, msg.args[1])
         return 1
 
@@ -652,7 +662,8 @@ def check(codeString, filename):
     # First, compile into an AST and handle syntax errors.
     try:
         tree = compile(codeString, filename, "exec", _ast.PyCF_ONLY_AST)
-    except SyntaxError, value:
+    except SyntaxError:
+        value = sys.exc_info()[1]
         msg = value.args[0]
 
         (lineno, offset, text) = value.lineno, value.offset, value.text
@@ -679,13 +690,15 @@ def check(codeString, filename):
     else:
         # Okay, it's syntactically valid.  Now check it.
         w = Checker(tree, filename)
-        w.messages.sort(lambda a, b: cmp(a.lineno, b.lineno))
+        sorting = [(msg.lineno, msg) for msg in w.messages]
+        sorting.sort()
+        w.messages = [msg for index, msg in sorting]
         valid_warnings = 0
 
         for warning in w.messages:
             if skip_warning(warning):
                 continue
-            print warning
+            print(warning)
             valid_warnings += 1
 
         return valid_warnings