A. Verify that the application manifest includes the correct stage definition with the 'privileges' parameter set to 'USAGE on the stage object. Also, within your Python code, use the 'snowflake.connector' to explicitly grant USAGE privilege from the application role to the stage.

B. Ensure the stage definition in the 'manifest.yml' file uses the fully qualified name of the stage (database.schema.stage_name), and verify that the consumer has imported the stage's database and schema into their environment. In Python, use the 'DESC STAGE command via a Snowflake connector to confirm existence and permissions.

C. Redeploy the application with the 'REPLACE' flag to automatically update the stage definition on the consumer side, and confirm that the application has sufficient privileges to access the storage integration associated with the stage. In Python, trap any 'Invalid stage name' exceptions and retry after a short delay.

D. Check the application's deployed version details in the consumer account's Snowflake UI to confirm the 'stage_name' parameter within the application manifest is defined correctly, and then within the Python code, make sure to utilize a fully qualified name when referring to the stage. Use Snowflake logging to write stage information to the event table.

E. Review the stage properties in both the provider and consumer accounts to ensure the storage integration is correctly configured and accessible from both sides. In the Python code, use the USE ROLE command to explicitly switch to the application's role before accessing the stage.