Make grader image dict a constant

common/lib/xmodule/xmodule/combined_open_ended_rubric.py

@@ -3,6 +3,11 @@ from lxml import etree
 
 log = logging.getLogger(__name__)
 
+GRADER_TYPE_IMAGE_DICT = {
+    'SA' : '/static/images/self_assessment_icon.png',
+    'PE' : '/static/images/peer_grading_icon.png',
+    'ML' : '/static/images/ml_grading_icon.png',
+    }
 
 class RubricParsingError(Exception):
     def __init__(self, msg):
@@ -171,18 +176,13 @@ class CombinedOpenEndedRubric(object):
                             rubric_categories[i]['options'][j]['grader_types'].append(grader_type)
 
         log.debug(rubric_categories)
-        grader_type_image_dict = {
-            'SA' : '/static/images/self_assessment_icon.png',
-            'PE' : '/static/images/peer_grading_icon.png',
-            'ML' : '/static/images/ml_grading_icon.png',
-        }
         html = self.system.render_template('open_ended_rubric.html',
             {'categories': rubric_categories,
              'has_score': True,
              'view_only': True,
              'max_score': max_score,
              'combined_rubric' : True,
-             'grader_type_image_dict' : grader_type_image_dict,
+             'grader_type_image_dict' : GRADER_TYPE_IMAGE_DICT,
             })
         return html