six
MIT License
Copyright (c) 2010-2020 Benjamin Peterson
Permission is hereby granted, free  of charge, to any person obtaining a copy of
  this software and associated documentation  files (the "Software"), to deal in
  the Software without restriction,  including without limitation the rights to
  use, copy, modify, merge, publish,  distribute, sublicense, and/or sell copies of
  the Software, and to permit persons  to whom the Software is furnished to do so,
  subject to the following  conditions:
The above copyright notice and this  permission notice shall be included in all
  copies or substantial portions of  the Software.
THE SOFTWARE IS PROVIDED "AS  IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED  TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  FOR A PARTICULAR PURPOSE AND  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  COPYRIGHT HOLDERS BE LIABLE FOR ANY  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  IN AN ACTION OF CONTRACT, TORT OR  OTHERWISE, ARISING FROM, OUT OF OR IN
  CONNECTION WITH THE SOFTWARE OR THE  USE OR OTHER DEALINGS IN THE SOFTWARE.
