add __ne__ implementation based on __eq__

theano/sparse/basic.py

@@ -333,6 +333,9 @@ class SparseConstantSignature(tuple):
                 (b.shape == y.shape) and
                 (abs(b - y).sum() < 1e-6 * b.nnz))
 
+    def __ne__(self, other):
+        return not self == other
+
     def __hash__(self):
         (a, b) = self
         return hash(type(self)) ^ hash(a) ^ hash(type(b))

theano/tensor/var.py

@@ -864,6 +864,9 @@ class TensorConstantSignature(tuple):
             # here).
             return (self.sum == other.sum) and np.all(d0 == d1)
 
+    def __ne__(self, other):
+        return not self == other
+
     def __hash__(self):
         t, d = self
         return hashtype(self) ^ hash(t) ^ hash(d.shape) ^ hash(self.sum)