chore: import upstream snapshot with attribution

tests/examples/test_sampling_examples.py

@@ -0,0 +1,33 @@
+import os
+import subprocess
+import sys
+import unittest
+
+EXAMPLE_ROOT = os.path.join(
+    os.path.dirname(os.path.relpath(__file__)),
+    "..",
+    "..",
+    "examples",
+    "graphbolt",
+    "quickstart",
+)
+
+
+def test_node_classification():
+    script = os.path.join(EXAMPLE_ROOT, "node_classification.py")
+    out = subprocess.run(["python", str(script)], capture_output=True)
+    assert (
+        out.returncode == 0
+    ), f"stdout: {out.stdout.decode('utf-8')}\nstderr: {out.stderr.decode('utf-8')}"
+    stdout = out.stdout.decode("utf-8")
+    assert float(stdout[-5:]) > 0.59
+
+
+def test_link_prediction():
+    script = os.path.join(EXAMPLE_ROOT, "link_prediction.py")
+    out = subprocess.run(["python", str(script)], capture_output=True)
+    assert (
+        out.returncode == 0
+    ), f"stdout: {out.stdout.decode('utf-8')}\nstderr: {out.stderr.decode('utf-8')}"
+    stdout = out.stdout.decode("utf-8")
+    assert float(stdout[-5:]) > 0.80