Recursive call in "parse_lt_objs" freezes the computer.

[MTKnife]

There's a typo in "parse_lt_objs" when the function calls itself on an "LTFigure" object--in that recursive call, the argument "lt_obj.objs" found in the original code at http://denis.papathanasiou.org/posts/2010.08.04.post.html has been replaced by "lt_obj", which starts an ugly endless loop.

Unfortunately, in the current version of PDFMiner, the "LTFigure" class has no ".objs" attribute. The proper fix is would seem be to to call the "analyze" method on the "LTFigure" object, which constructs and returns the (internal) "_.objs" attribute, but I'm not positive it's working correctly--my documents may not have "LTFigures" that actually contain child objects.