gh-142197: Doc: Add missing import statement in importlib.metadata overview (#142208)

Co-authored-by: Edgar Ramírez Mondragón <edgarrm358@gmail.com>
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>

Author: 3 people

Doc/library/importlib.metadata.rst

@@ -90,6 +90,7 @@ collection of :ref:`EntryPoint <entry-points>` objects.
 
 You can get the :ref:`metadata for a distribution <metadata>`::
 
+    >>> from importlib.metadata import metadata  # doctest: +SKIP
     >>> list(metadata('wheel'))  # doctest: +SKIP
     ['Metadata-Version', 'Name', 'Version', 'Summary', 'Home-page', 'Author', 'Author-email', 'Maintainer', 'Maintainer-email', 'License', 'Project-URL', 'Project-URL', 'Project-URL', 'Keywords', 'Platform', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Classifier', 'Requires-Python', 'Provides-Extra', 'Requires-Dist', 'Requires-Dist']