Close#11

Sample pictures:

Before submitting a PR mark the checkboxes for the items you've done (if you
think a checkbox does not apply, then leave it unchecked):

• The commits are consistent with ourcontribution guidelines.

• You've runM-x checkdoc and fixed any warnings in the code you've written.
• You've updated the changelog (if adding/changing user-visible functionality).
• You've updated the readme (if adding/changing user-visible functionality).

Thanks!