docs: describe fetching existing export status

docs/gl_objects/projects.rst

@@ -289,6 +289,14 @@ generated by GitLab you need to:
     with open('/tmp/export.tgz', 'wb') as f:
         export.download(streamed=True, action=f.write)
 
+You can also get the status of an existing export, regardless of
+whether it was created via the API or the Web UI::
+
+    project = gl.projects.get(my_project)
+
+    # Gets the current export status
+    export = project.exports.get()
+
 Import the project into the current user's namespace::
 
     with open('/tmp/export.tgz', 'rb') as f: