Add types to commit.py spit parents into list and tuple types

Author: Yobmod

git/objects/commit.py

@@ -129,6 +129,7 @@ def __init__(self, repo, binsha, tree=None, author=None, authored_date=None, aut
             self.message = message
         if parents is not None:
             self.parents = parents
+            self.parents_list = list(parents)
         if encoding is not None:
             self.encoding = encoding
         if gpgsig is not None: