diff --git a/common/lib/xmodule/xmodule/peer_grading_module.py b/common/lib/xmodule/xmodule/peer_grading_module.py
index 99180720dc..0e6beb8c74 100644
--- a/common/lib/xmodule/xmodule/peer_grading_module.py
+++ b/common/lib/xmodule/xmodule/peer_grading_module.py
@@ -82,7 +82,6 @@ class PeerGradingModule(XModule):
         if isinstance(self.is_graded, basestring):
             self.is_graded = (self.is_graded in TRUE_DICT)
 
-        #TODO: do we only want to allow this for single locations?
         display_due_date_string = self.metadata.get('due', None)
         grace_period_string = self.metadata.get('graceperiod', None)
 
diff --git a/common/lib/xmodule/xmodule/timeinfo.py b/common/lib/xmodule/xmodule/timeinfo.py
index dcb198337f..6c6a72e700 100644
--- a/common/lib/xmodule/xmodule/timeinfo.py
+++ b/common/lib/xmodule/xmodule/timeinfo.py
@@ -8,8 +8,14 @@ log = logging.getLogger(__name__)
 
 class TimeInfo(object):
     """
-    This is a simple object that stores datetime information for an XModule
+    This is a simple object that calculates and stores datetime information for an XModule
     based on the due date string and the grace period string
+
+    So far it parses out three different pieces of time information:
+        self.display_due_date - the 'official' due date that gets displayed to students
+        self.grace_period - the length of the grace period
+        self.close_date - the real due date
+
     """
     def __init__(self, display_due_date_string, grace_period_string):
         if display_due_date_string is not None: