A solution that I found over on Stackoverflow was the following [proposed here][1] for a UnicodeDecodingError, which did work for me:

    (setenv "LANG" "en_US.UTF-8")
    (setenv "LC_ALL" "en_US.UTF-8")
    (setenv "LC_CTYPE" "en_US.UTF-8")

I only actually required the first of the three lines in my case.

Further suggestions specific to Python are in [this post][2], namely to add this to your `.emacs` init file:

    (setenv "PYTHONIOENCODING" "utf-8")


  [1]: https://emacs.stackexchange.com/questions/3878/unicodedecodeerror-in-my-inferior-python-buffer?rq=1
  [2]: https://stackoverflow.com/questions/14172576/why-unicodeencodeerror-raised-only-in-emacss-python-shell