[Python] python psycopg cursor : str is not assignable to LiteralString

I want to switch from synchronous db calls to asynchronous db calls. I don't want to change my query builder. My query builder outputs a sql query as a string (actually in reality it outputs a query with '%s' to escape parameters and the escaped parameters in a list).

This works great in psycopg2 but does not seem to work in psycopg since the cursor does not want to take an "str" as the query (quite annoying). How can I make it work ?

import asyncio
import psycopg


class MyQueryBuilderObj:
def getFinalQuery(self) -> str:
return "SELECT * FROM test_table"

async def fetch_data_from_db():
qb_obj = MyQueryBuilderObj()
async with await psycopg.AsyncConnection.connect("dbname=test user=postgres password=yourpassword host=localhost") as aconn:
async with aconn.cursor() as acur:
await acur.execute(qb_obj.getFinalQuery())
result = await acur.fetchone()
return result

async def main():
try:
result = await fetch_data_from_db()
print("Fetched data:", result)
except Exception as e:
print("An error occurred:", e)

if __name__ == "__main__":
asyncio.run(main())


Issue at "acur.execute" :

Argument of type "str" cannot be assigned to parameter "query" of type "Query" in function "execute"
Type "str" is not assignable to type "Query"
"str" is not assignable to "LiteralString"
"str" is not assignable to "bytes"
"str" is not assignable to "SQL"
"str" is not assignable to "Composed"


Version :

• psycopg 3.2.5
• python 3.12.5

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