Merge pull request matplotlib#2581 from leejjoon/affine_base_eq

AffineBase.__eq__ should not raise an exception when the other does not ...

Author: mdboom

lib/matplotlib/transforms.py

@@ -1559,7 +1559,7 @@ def _concat(a, b):
         return np.dot(b, a)
 
     def __eq__(self, other):
-        if other.is_affine:
+        if getattr(other, "is_affine", False):
             return np.all(self.get_matrix() == other.get_matrix())
         return NotImplemented