Method difference

crates/vm/src/builtins/set.rs:266–272

(&self, other: ArgIterable, vm: &VirtualMachine)

    }

    pub(super) fn difference(&self, other: ArgIterable, vm: &VirtualMachine) -> PyResult<Self> {
        let set = self.copy();
        for item in other.iter(vm)? {
            set.content.delete_if_exists(vm, &*item?)?;
        }
        Ok(set)
    }

    pub(super) fn symmetric_difference(
        &self,