The default behavior to use the distributed wurlitzer when available (i.e., on UNIX) causes intermittent cell execution timeouts when using nbconvert.

While I can copy paste the error log, deleting the module file --or better yet-- replacing it with the upstream one at https://github.com/minrk/wurlitzer seems to fix it. I believe the correct approach here (that also properly acknowledges the original author) would be to have wurlitzer as an external dependency. Unless of course there are custom changes in the distributed version?