fix windows numpy import and add node timestamps

tests/test_numpy_compat.py

@@ -0,0 +1,8 @@
+import backend  # noqa: F401
+import numpy as np
+
+
+def test_numpy_compat_aliases_are_available_after_backend_import():
+    assert np.complex is complex
+    assert np.float is float
+    assert np.int is int