How to get the AST-tree instead of a list when parsing in Python with ANTLR?

How to get the AST-tree instead of a list when parsing in Python with ANTLR?

References

Reference NO 1

http://stackoverflow.com/questions/15206110/how-to-get-the-ast-tree-instead-of-a-list-when-parsing-in-python-with-antlr

Reference NO 2

http://stackoverflow.com/questions/16486342/building-a-parse-tree-in-antlr-with-python-target

Reference NO 3

http://stackoverflow.com/questions/15081981/what-is-the-advantage-of-using-ast-tree-walker-for-translating-a-dsl-instead-o

Reference NO 4

http://stackoverflow.com/questions/14863279/antlr-v-3-use-of-syntactic-predicate-for-lookahead

Reference NO 5

http://stackoverflow.com/questions/17856137/how-to-draw-a-parse-tree-when-a-small-python-file-is-parsed

Reference NO 6

http://www.antlr3.org/grammar/list.html

Reference NO 7

#EANF#

Reference NO 8

#EANF#