Add __getattr__ to DummySpecies. Fixes #3167.

Author: Shyue Ping Ong

pymatgen/core/periodic_table.py

@@ -1414,6 +1414,9 @@ def __init__(
         else:
             self._spin = spin
 
+    def __getattr__(self, attr):
+        raise AttributeError
+
     def __lt__(self, other):
         """
         Sets a default sort order for atomic species by Pauling electronegativity,

pymatgen/core/tests/test_periodic_table.py

@@ -515,6 +515,10 @@ def test_init(self):
         self.specie2 = DummySpecies("X", 2, spin=3)
         assert self.specie2.spin == 3
 
+    def test_attr(self):
+        with pytest.raises(AttributeError):
+            _ = self.specie2.ionic_radius
+
     def test_eq(self):
         assert DummySpecies("Xg") != DummySpecies("Xh")
         assert DummySpecies("Xg") != DummySpecies("Xg", 3)