nlhepler/pydot — pull request #8 by gustavla (2014-07-30 23:27:52+00:00)
Title: Fixes syntax error in older versions of graphviz.

Older versions of graphviz (tested on version 2.26.3 (20100126.1600)) complains when an attribute is empty without quotes. `[label=]` fails but `[label=""]` works, so the `quote_if_necessary` function has been updated to accommodate this.