Generate a correct and concise answer for the question based on the words in the context.

[EX Q]: Context : Nohra Puyana Bickenbach (born 29 May 1955) is the wife of the 30th President of Colombia, Andrés Pastrana Arango, and served as First Lady of Colombia from 1998 to 2002. 
Question : What is Nohra Puyana Bickenbach's spouse's name?
[EX A]: Andrés Pastrana Arango

[EX Q]: Context : The Votive Panel of Jan Očko of Vlašim is a Gothic panel painting currently housed in the National Gallery in Prague, Czech Republic. 
Question : What is the name of the place where Votive Panel of Jan Očko of Vlašim can be found?
[EX A]: National Gallery in Prague

[EX Q]: Context : Copyleft (a play on the word copyright) is the practice of offering people the right to freely distribute copies and modified versions of a work with the stipulation that the same rights be preserved in derivative works down the line. 
Question : The Copyleft is based upon what?
[EX A]:
copyright