Merge pull request #3145 from heplesser/fix-slow-ipython

Stop IPython from time consuming deep inspection of NodeCollection objects

pynest/nest/lib/hl_api_types.py

@@ -547,6 +547,13 @@ def __getattr__(self, attr):
         if not self:
             raise AttributeError("Cannot get attribute of empty NodeCollection")
 
+        # IPython looks up this method when doing pretty printing
+        # As long as we do not provide special methods to support IPython prettyprinting,
+        # HTML-rendering, etc, we stop IPython from time-consuming checks by raising an
+        # exception here. The exception must *not* be AttributeError.
+        if attr == "_ipython_canary_method_should_not_exist_":
+            raise NotImplementedError("_ipython_canary_method_should_not_exist_")
+
         if attr == "spatial":
             metadata = sli_func("GetMetadata", self._datum)
             val = metadata if metadata else None