list += operator generates Error #1351
Description
Feature
a = [3]
a += a
print(a)The code above generates the following error:
(list += operator)
actual
Hyeockz:RustPython hyeockjinkim$ cargo run b.py
Finished dev [unoptimized + debuginfo] target(s) in 0.11s
Running `target/debug/rustpython b.py`
thread 'main' panicked at 'already mutably borrowed: BorrowError', src/libcore/result.rs:999:5
note: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.expected
[3, 3]