Why is "gs" is not defined in a python script accessing google cloud storage? - google-cloud-storage

Question

The purpose of the script is to import products to google vision API product search by using a CSV file containing information about the products. In this example the cloud storage address is the default one given in the documentation(https://cloud.google.com/vision/product-search/docs/create-product-set-search-products#using_a_dataset)(https://cloud.google.com/vision/product-search/docs/create-product-set#using_bulk_import_to_create_a_product_set_with_products). When I try to set the cvs_file_uri variable, vscode states that "gs" is not defined, despite google cloud storage being imported.
from google.cloud import vision
from google.protobuf import field_mask_pb2 as field_mask
from google.cloud import storage
#"""Import images of different products in the product set.
#Args:
# project_id: Id of the project.
# location: A compute region name.
# gcs_uri: Google Cloud Storage URI.
# Target files must be in Product Search CSV format.
#"""
client = vision.ProductSearchClient()
# A resource that represents Google Cloud Platform location.
location_path = f"projects/[project id]/locations/europe-west1"
# Set the input configuration along with Google Cloud Storage URI
############error is on the 2 lines below
gcs_source = vision.ImportProductSetsGcsSource(
csv_file_uri=gs://cloud-samples-data/vision/product_search/product_catalog.csv)
########################
input_config = vision.ImportProductSetsInputConfig(
gcs_source=gcs_source)
# Import the product sets from the input URI.
response = client.import_product_sets(
parent=location_path, input_config=input_config)
print('Processing operation name: {}'.format(response.operation.name))
# synchronous check of operation status
result = response.result()
print('Processing done.')
for i, status in enumerate(result.statuses):
print('Status of processing line {} of the csv: {}'.format(
i, status))
# Check the status of reference image
# `0` is the code for OK in google.rpc.Code.
if status.code == 0:
reference_image = result.reference_images[i]
print(reference_image)
else:
print('Status code not OK: {}'.format(status.message))