I found that simply importing pandas prevents files from being opened by the OS. By opening I mean that I want a Windows window to open and display an image for me. Instead nothing happens and the script finishes with no errors. import os import pandas # works fine without this line os.startfile("img.png") # windows-only way to open I found this when using graphviz to render a graph to an image and open it after. graphviz uses os.startfile under the hood. What could pandas be doing here? python: 3.12.9 pandas: 2.2.3 Continue reading...