New error message when saving invalid expressions

src/blosc2/lazyexpr.py

@@ -1990,8 +1990,6 @@ def _new_expr(cls, expression, operands, guess, out=None, where=None):
             print(f"shape: {new_expr.shape}, dtype: {new_expr.dtype}")
             new_expr._shape = new_expr.shape
             new_expr._dtype = new_expr.dtype
-            new_expr.expression = expression
-            new_expr.operands = operands
         else:
             # Create a new LazyExpr object
             new_expr = cls(None)

tests/ndarray/test_lazyexpr.py

@@ -552,7 +552,7 @@ def test_save_unsafe():
     # during loading time (tested above).
     with pytest.raises(Exception) as excinfo:
         expr.save(urlpath=urlpath)
-    assert expr.expression in str(excinfo.value)
+    assert "invalid syntax" in str(excinfo.value)
 
     for urlpath in disk_arrays:
         blosc2.remove_urlpath(urlpath)