Why did postgres query stop working in Python?

Question

Python

Hello.
I am using connection to Postgresql 11 via psycopg2.

The code worked fine before.

def get_switch(self):
        with self.conn:
            self.cursor.execute('SELECT switch FROM switches WHERE id=7')
            return self.cursor.fetchone()[0]    

def change_switch(self):
        with self.conn:
            switch = self.get_switch()
            self.cursor.execute('UPDATE switches SET switch=%s WHERE id=7', (not switch,))
            self.conn.commit()

now throws an error

in get_switch
with self.conn:
psycopg2.ProgrammingError: the connection cannot be re-entered recursively

As I understand it, he swears that two times with self.conn: is used.
Why did the exact same lines work well before?
And it doesn't work now?

Answer 1

It swears precisely at the fact that another with conn was launched inside one with conn. Check your code.
Judging by the documentation and googling reviews, this error began to be issued from version 2.9, so maybe they just ran it on an older version earlier, so they didn’t meet it.