Method ensure_connection_open

crates/stdlib/src/_sqlite3.rs:2355–2364

(&self, vm: &VirtualMachine)

        }

        fn ensure_connection_open(&self, vm: &VirtualMachine) -> PyResult<()> {
            if self.connection.is_closed() {
                Err(new_programming_error(
                    vm,
                    "Cannot operate on a closed database".to_owned(),
                ))
            } else {
                Ok(())
            }
        }

        #[pymethod]
        fn read(