minor fixes

python_ast/download_prepare.sh

@@ -12,14 +12,11 @@ wget http://files.srl.inf.ethz.ch/data/py150.tar.gz
 # extract abstract syntax trees
 tar -xzf py150.tar.gz
 
-# change to extracted directory
-cd py150
-
 # convert ast to bracket notation
-python ../parse_json.py --inputfile python100k_train.json > python_ast.bracket
+python3 parse_json.py --inputfile python100k_train.json > python_ast.bracket
 
 # convert ast to bracket notation
-python ../parse_json.py --inputfile python50k_eval.json >> python_ast.bracket
+python3 parse_json.py --inputfile python50k_eval.json >> python_ast.bracket
 
 # sort the trees ascending by their size
-../sort_dataset.sh python_ast.bracket
\ No newline at end of file
+./sort_dataset.sh python_ast.bracket