[Python] {{ ds }} isn't interpreted in my airflow dag

My goal is to dynamically create some SFTPToS3Operator to retrieve files from a server to Amazon S3.

For instance, ,my filename is xxx_date_hours_minutes_seconds.csv, so I want to fetch filename from the server to use it in the SFTPToS3Operator operator.

The main problem is that the {{ ds }} is not interpreted

with DAG(...)
as dag:
init_task = DummyOperator(task_id='dag_start')
alertPerfOperatorsTask = list_files_to_transfer()
init_task >> alertPerfOperatorsTask


The goal of list_files_to_transfer is to create a list of task, one task for each file :

def list_files_to_transfer():
logger = logging.getLogger('airflow.task')
yesterday_date = '{{ macros.ds_add(ds, -1) }}'
logger.info("yesterday_date: " + yesterday_date)
sftp_hook = SFTPHook(ssh_conn_id='SFTP__gas__PointBreakExporter')
with sftp_hook.get_conn() as sftp_client:
remote_path = 'out/IQUAL_DEV/'
...
return alertPerfOperatorsTask (list of SFTPToS3Operator)


If I look at my log, I get :

INFO - yesterday_date: `{{ macros.ds_add(ds, -1) }}` instead of yesterday_date: 2025-03-19


and of course I am using this date to find file but obvioulsy didn't find any file named xxx_{{ macros.ds_add(ds, -1) }}.csv

I don't understand why {{ macros.ds_add(ds, -1) }} isn't interpreted

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