Fixed click issue suggested by
https://github.com/pallets/click/pull/2130/commits/60a5eafaf5f2a71b2a8a4f93ad1faefb2b8b0f76#diff-0140337741a334b642a5170e3bd7c408eea4bb4394df9226cd033fae8f5c0a19L394
Close #10 (closed)