change pickle read/load to binary; fixes a py3 bug

RealSpaceInterface/Calc2D/Database.py

@@ -14,22 +14,22 @@ def __init__(self, directory, db_file="database.dat"):
         self.db_path = os.path.join(directory, db_file)
         if not os.path.exists(self.db_path):
             logging.info("No database found; Creating one at {}.".format(self.db_path))
-            with open(self.db_path, "w") as f:
+            with open(self.db_path, "wb") as f:
                 pickle.dump(dict(), f)
 
         self.db = self.__read_database()
 
     def __read_database(self):
-        with open(self.db_path) as f:
+        with open(self.db_path, "rb") as f:
             return pickle.load(f)
 
     def __write_database(self):
-        with open(self.db_path, "w") as f:
+        with open(self.db_path, "wb") as f:
             pickle.dump(self.db, f)
 
     def __create_file(self, data):
         filename = str(uuid.uuid4())
-        with open(os.path.join(self.directory, filename), "w") as f:
+        with open(os.path.join(self.directory, filename), "wb") as f:
             pickle.dump(data, f)
         return filename
 
@@ -40,7 +40,7 @@ def __getitem__(self, key):
         frozen_key = self.__get_frozen_key(key)
         if frozen_key in self.db:
             filename = self.db[frozen_key]
-            with open(os.path.join(self.directory, filename)) as f:
+            with open(os.path.join(self.directory, filename), "rb") as f:
                 return pickle.load(f)
         else:
             raise KeyError("No data for key: {}".format(key))
@@ -55,4 +55,4 @@ def __contains__(self, key):
         Return whether `self` contains a record
         for the given `key`.
         """
-        return self.__get_frozen_key(key) in self.db
+        return self.__get_frozen_key(key) in self.db