Fix for #8

Author: cdmayer

src/onedrivesdk/session.py

@@ -81,6 +81,7 @@ def save_session(self, **save_session_kwargs):
             # pickle.HIGHEST_PROTOCOL is binary format. Good perf.
             pickle.dump(self, session_file, pickle.HIGHEST_PROTOCOL)
 
+    @staticmethod
     def load_session(**load_session_kwargs):
         """Save the current session.
         IMPORTANT: This implementation should only be used for debugging.