Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/matplotlib/tests/test_backend_nbagg.py

@@ -0,0 +1,28 @@
+import os
+from pathlib import Path
+import subprocess
+from tempfile import TemporaryDirectory
+
+import pytest
+
+nbformat = pytest.importorskip('nbformat')
+
+# From https://blog.thedataincubator.com/2016/06/testing-jupyter-notebooks/
+
+
+def test_ipynb():
+    nb_path = Path(__file__).parent / 'test_nbagg_01.ipynb'
+
+    with TemporaryDirectory() as tmpdir:
+        out_path = Path(tmpdir, "out.ipynb")
+        subprocess.check_call(
+            ["jupyter", "nbconvert", "--to", "notebook",
+             "--execute", "--ExecutePreprocessor.timeout=500",
+             "--output", str(out_path), str(nb_path)],
+            env={**os.environ, "IPYTHONDIR": tmpdir})
+        with out_path.open() as out:
+            nb = nbformat.read(out, nbformat.current_nbformat)
+
+    errors = [output for cell in nb.cells for output in cell.get("outputs", [])
+              if output.output_type == "error"]
+    assert not errors