revert re-raising AttributeError

Author: jbrockmendel

pandas/core/groupby/generic.py

@@ -261,7 +261,7 @@ def aggregate(self, func=None, *args, **kwargs):
 
             try:
                 return self._python_agg_general(func, *args, **kwargs)
-            except (AssertionError, TypeError, AttributeError):
+            except (AssertionError, TypeError):
                 raise
             except IndexError:
                 raise