Method setitem_by_slice

crates/stdlib/src/mmap.rs:1552–1595

(
            &self,
            slice: &SaturatedSlice,
            value: PyObjectRef,
            vm: &VirtualMachine,
        )

        }

        fn setitem_by_slice(
            &self,
            slice: &SaturatedSlice,
            value: PyObjectRef,
            vm: &VirtualMachine,
        ) -> PyResult<()> {
            let (range, step, slice_len) = slice.adjust_indices(self.__len__());

            let bytes = bytes_from_object(vm, &value)?;

            if bytes.len() != slice_len {
                return Err(vm.new_index_error("mmap slice assignment is wrong size"));
            }

            if slice_len == 0 {
                // do nothing
                Ok(())
            } else if step == 1 {
                self.try_writable(vm, |mmap| {
                    (&mut mmap[range])
                        .write(&bytes)
                        .map_err(|err| err.to_pyexception(vm))?;
                    Ok(())
                })?
            } else {
                let mut bi = 0; // bytes index
                if step.is_negative() {
                    for i in range.rev().step_by(step.unsigned_abs()) {
                        self.try_writable(vm, |mmap| {
                            mmap[i] = bytes[bi];
                        })?;
                        bi += 1;
                    }
                } else {
                    for i in range.step_by(step.unsigned_abs()) {
                        self.try_writable(vm, |mmap| {
                            mmap[i] = bytes[bi];
                        })?;
                        bi += 1;
                    }
                }
                Ok(())
            }
        }
    }

    impl Representable for PyMmap {