ModuleNotFoundError: No module named 'requests'

🐛 Bug

Error when running demo/Mask_R-CNN_demo.ipynb from a docker instance with jupyter:

ModuleNotFoundError: No module named 'requests'

To Reproduce

Steps to reproduce the behavior:

1. Build image with jupyter as in docs
2. Run a docker instance of this image simliar as explained in [docs] but using docker instead of nvidia-docker (https://github.com/facebookresearch/maskrcnn-benchmark/blob/master/INSTALL.md).
3. Run first cell of demo/Mask_R-CNN_demo.ipynb

Expected behavior

Code executed without errors.

Environment

• CUDA/cuDNN version: 10.0 / 7
• GPU models and configuration: no GPU

Additional context

Adding the following new line in docker/docker-jupyter/Dockerfile fixes the problem:

RUN pip install requests