Refactor to use wrapping classes

new_xmodule/sample_xmodules.py

 import xmodule
 from xmodule import progress
 
-def XModule():
+class XModule():
+    class StudentWidget(ResourceTemplate):
         def __init__(self, content, policy, state, child_pointers, preferences):
             self.content = content
             self.policy = policy
@@ -26,8 +27,7 @@ def XModule():
             return self._views[context]
 
 
-def XModuleEditor():
-
+    class EditorWidget(ResourceTemplate):
         @xmodule.register_view('edit')
         def edit(self):
             return self.render_template(
@@ -77,7 +77,8 @@ def XModuleEditor():
             else:
                 self.policy[data['name']] = self.policy[data['value']]
 
-def SequenceEditor(XModuleEditor, ResourceTemplate):
+class Sequence():
+    class EditorWidget(XModule.EditorWidget):
 
         @xmodule.register_view('edit')
         def edit(self):
@@ -91,7 +92,7 @@ def SequenceEditor(XModuleEditor, ResourceTemplate):
         def empty_view(self):
             return None
 
-def SequenceModule(XModule, ResourceTemplate):
+    class StudentWidget(XModule.StudentWidget):
 
         @property
         def visited(self):
@@ -131,7 +132,8 @@ def SequenceModule(XModule, ResourceTemplate):
             })
 
 
-def ChemistryEquationModule(XModule, ResourceTemplateModule):
+class ChemistryEquation(XModule):
+    class ChemistryEquationModule(XModule.StudentWidget):
 
         def __init__(self, definition, policy, state, preferences):
             self.state = state