[Python] Sqlalchemy and psycopg2: pandas.read_sql_query "dict is not a sequence" error with...

Package Versions:

• SQLAlchemy 2.0.40
• pandas 2.2.3
• psycopg2-binary 2.9.10

I am trying to run a query using pandas' native param substitution, but I can't seem to get it to run without erroring. I tried simplifying the query to:

select *
FROM public.bq_results br
WHERE cast("eventDate" as date) between
TO_DATE('%test_start_date', 'YYYYMMDD') AND TO_DATE('%test_end_date', 'YYYYMMDD')
limit 10000


but I get error:

TypeError: dict is not a sequence


when running:

df = pd.read_sql_query(query, self.__engine, params={"test_start_date": "20250101", "test_end_date": "20250131"})


where

self.__engine = create_engine(f'postgresql://{self.user}:{self.password}@{self.host}:{self.port}/{self.database}')

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