move safe_unicode to py3compat

IPython/kernel/zmq/zmqshell.py

@@ -472,27 +472,6 b' class KernelMagics(Magics):'
         else:
             print("Autosave disabled")
 
-def safe_unicode(e):
-    """unicode(e) with various fallbacks. Used for exceptions, which may not be
-    safe to call unicode() on.
-    """
-    try:
-        return unicode(e)
-    except UnicodeError:
-        pass
-
-    try:
-        return py3compat.str_to_unicode(str(e))
-    except UnicodeError:
-        pass
-
-    try:
-        return py3compat.str_to_unicode(repr(e))
-    except UnicodeError:
-        pass
-
-    return u'Unrecoverably corrupt evalue'
-
 
 class ZMQInteractiveShell(InteractiveShell):
     """A subclass of InteractiveShell for ZMQ."""
@@ -572,7 +551,7 b' class ZMQInteractiveShell(InteractiveShell):'
         exc_content = {
             u'traceback' : stb,
             u'ename' : unicode(etype.__name__),
-            u'evalue' : safe_unicode(evalue)
+            u'evalue' : py3compat.safe_unicode(evalue),
         }
 
         dh = self.displayhook

IPython/utils/py3compat.py

@@ -50,6 +50,27 b' def _modify_str_or_docstring(str_change_func):'
         return doc
     return wrapper
 
+def safe_unicode(e):
+    """unicode(e) with various fallbacks. Used for exceptions, which may not be
+    safe to call unicode() on.
+    """
+    try:
+        return unicode(e)
+    except UnicodeError:
+        pass
+
+    try:
+        return py3compat.str_to_unicode(str(e))
+    except UnicodeError:
+        pass
+
+    try:
+        return py3compat.str_to_unicode(repr(e))
+    except UnicodeError:
+        pass
+
+    return u'Unrecoverably corrupt evalue'
+
 if sys.version_info[0] >= 3:
     PY3 = True