fix(retail): add region tag for Python - Update import user events from big query (#13493)

* Update search_with_pagination.py

* Update import_user_events_big_query.py

* lint

---------

Co-authored-by: Katie McLaughlin <katie@glasnt.com>

Author: rebeccaellis

retail/interactive-tutorials/events/import_user_events_big_query.py

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# [START retail_import_user_events_from_big_query]
 
 import argparse
 
@@ -97,6 +99,8 @@ def import_user_events_from_big_query():
 
     import_user_events_from_big_query()
 
+# [END retail_import_user_events_from_big_query]
+
 
 if __name__ == "__main__":
     parser = argparse.ArgumentParser()