Why am I seeing extra backlashes after I paste my code into Tot?

Try changing the dot you want to use to “Plan text / Markdown” mode instead of “Rich Text” mode by toggling the “a” icon at the bottom right of the dot.

Then paste the code into the dot using:

This will avoid the backlashes being added.

You can also change the default "paste text" into "paste as plain text" by adding a per-app keyboard shortcut in the OS's keyboard settings, please see Create keyboard shortcuts for apps on Mac.

Other useful shortcuts for Tot is available here