This Academic Free License (the "License") applies to any original work of 
authorship (the "Original Work") whose owner (the "Licensor") has placed 
the following notice immediately following the copyright notice for the 
Original Work:

Licensed under the Academic Free License version 2.1

1) Grant of Copyright License. Licensor hereby grants You a world-wide, 
royalty-free, non-exclusive, perpetual, sublicenseable license to do the  
following:

a) to reproduce the Original Work in copies;
b) to prepare derivative works ("Derivative Works") based upon the Original Work;
c) to distribute copies of the Original Work and Derivative Works to the public;
d) to perform the Original Work publicly; and
e) to display the Original Work publicly.

2) Grant of Patent License. Licensor hereby grants You a world-wide, 
royalty-free, non-exclusive, perpetual, sublicenseable license, under 
patent claims owned or controlled by the Licensor that are embodied in the 
Original Work as furnished by the Licensor, to make, use, sell and offer 
for sale the Original Work and Derivative Works.

3) Grant of Source Code License. The term "Source Code" means the preferred 
form of the Original Work for making modifications to it and all available 
documentation describing how to modify the Original Work. Licensor hereby 
agrees to provide a machine-readable copy of the Source Code of the Original 
Work along with each copy of the Original Work that Licensor distributes. 
Licensor reserves the right to satisfy this obligation by placing a machine
-readable copy of the Source Code in an information repository reasonably 
calculated to permit inexpensive and convenient access by You for as long 
as Licensor continues to distribute the Original Work, and by publishing 
the address of that information repository in a notice immediately following
the copyright notice that applies to the Original Work.

4) Exclusions From License Grant. Neither the names of Licensor, nor the 
names of any contributors to the Original Work, nor any of their  trademarks 
or service marks, may be used to endorse or promote products derived from
this Original Work without express prior written permission of the Licensor.
Nothing in this License shall be deemed to grant any rights to trademarks,
copyrights, patents, trade secrets or any other intellectual property of 
Licensor except as expressly stated herein. No patent license is granted to 
make, use, sell or offer to sell embodiments of any patent claims other than
the licensed claims defined in Section 2. No right is granted to the trademarks
of Licensor even if such marks are included in the Original Work. Nothing in
this License shall be interpreted to prohibit Licensor from licensing under
different terms from this License any Original Work that Licensor otherwise
would have a right to license.

5) This section intentionally omitted.

For more details visit : https://spdx.org/licenses/AFL-2.1.html