Error after sending visual selection to ipython with vim splits

[ghost]

I noticed an error after sending a visual selection with python code containing imports. To reproduce this issue:

1 - Initiate tmux and create two panes (in my case, I hit C-b+").
2 - In the first pane, open a file with vim (I personally use neovim). In the second pane, start a session with ipython.
3 - In the pane you started vim, create a vertical split with vim (C-W v)
4 - (Optional) Open another file in the second vertical split created in step 3.
5 - Write some python imports in the first part of the vertical split

import sys
import os

6 - Visually select those lines and send them to the ipython pane
7 - This will trigger an error

I attach a couple of screenshots to make the explanation easier to follow.

For some reason, this only happens with imports.

Version information: tmux 2.0, Ubuntu GNOME 15.10, latest version of slimux.

Thanks