Method difference_update

crates/vm/src/builtins/set.rs:411–423

(
        &self,
        others: impl core::iter::Iterator<Item = ArgIterable>,
        vm: &VirtualMachine,
    )

    }

    fn difference_update(
        &self,
        others: impl core::iter::Iterator<Item = ArgIterable>,
        vm: &VirtualMachine,
    ) -> PyResult<()> {
        for iterable in others {
            let items = iterable.iter(vm)?.collect::<Result<Vec<_>, _>>()?;
            for item in items {
                self.content.delete_if_exists(vm, &*item)?;
            }
        }
        Ok(())
    }

    fn symmetric_difference_update(
        &self,