updated for version 7.3.698

Problem:    Python 3 does not preserve state beween commands.
Solution:   Preserve the state. (Paul Ollis)

src/if_python3.c

@@ -731,8 +731,12 @@ Python3_Init(void)
 #else
 	PyMac_Initialize();
 #endif
-	/* initialise threads, must be after Py_Initialize() */
+	/* Initialise threads, and save the state using PyGILState_Ensure.
+	 * Without the call to PyGILState_Ensure, thread specific state (such
+	 * as the system trace hook), will be lost between invocations of
+	 * Python code. */
 	PyEval_InitThreads();
+	pygilstate = PyGILState_Ensure();
 
 #ifdef DYNAMIC_PYTHON3
 	get_py3_exceptions();