For a long time it was easy to spot Python GUI programs. They were the ones either uselessly spinning (because Python's signal implementation span when multi-threaded) or else frozen (because to avoid this spinning someone decided not to multi-thread the code and thus the GUI stopped updating)
In theory this is fixed in a new enough Python. If you have a new enough Python, and if your Python programs were updated to take advantage. So mostly, not yet.
It was also way too easy to spot Python programs written at Red Hat to replace older C admin tools. The C admin tool might react to unexpected contents of a configuration file by segfaulting, but more likely it would ignore the unexpected element altogether. Ignoring unexpected things in C is really easy, it's often the default outcome. In Python you'd get a stacktrace, but of course only /after/ the program had truncated your file ready to write its output. The practical result was that the tools were now much less reliable, such tools ate my NTP configuration, printer settings and other useful stuff. Nice.