Clean up JSON Schema Compiler.

tools/json_schema_compiler/cpp_type_generator.py

Index: tools/json_schema_compiler/cpp_type_generator.py
diff --git a/tools/json_schema_compiler/cpp_type_generator.py b/tools/json_schema_compiler/cpp_type_generator.py
index efb712ee7289e55a43c8efc52472ecae596e8789..4c0306d18bb04ca68c8161ec5a4040ff1743d1b2 100644
--- a/tools/json_schema_compiler/cpp_type_generator.py
+++ b/tools/json_schema_compiler/cpp_type_generator.py
@@ -3,10 +3,9 @@
 # found in the LICENSE file.
 
 from code import Code
-from model import Namespace, PropertyType, Type
+from model import PropertyType
 import cpp_util
 from json_parse import OrderedDict
-from operator import attrgetter
 import schema_util
 
 class _TypeDependency(object):
@@ -21,6 +20,7 @@ class _TypeDependency(object):
   def GetSortKey(self):
     return '%s.%s' % (self.type_.namespace.name, self.type_.name)
 
+
 class CppTypeGenerator(object):
   """Manages the types of properties and provides utilities for getting the
   C++ type out of a model.Property