This internal method is used in plt.pause() and BlockingInput class (I don't know what the latter does). The problem is approximately since Matplotlib 2.0.0 (but I don't know what exactly has changed) ...
UPDATE: Version 1.0.0 now has some small but useful updates. Download and try the source code or the precompiled Windows executable file available here. IMPORTANT NOTE: TESS bandpass was added to ...