Remove redundant chdir in py file
Remove redundant chdir in py file

chunmun/tree-builder-builder,dglazkov/tree-builder-builder,loyso/tree-builder-builder,loyso/tree-builder-builder,dglazkov/tree-builder-builder,chunmun/tree-builder-builder,loyso/tree-builder-builder,dglazkov/tree-builder-builder,chunmun/tree-builder-builder