Update Dockerfile to Python 3.10

python-3.10-slim

Dockerfile with python:3.10-slim

Dockerfile with python:3.9.5-slim

python-3.9.5-slim

clean up imports

Dockerfile with python:3.9.2-slim

python-3.9.2-slim

use html escape

Dockerfile with python:3.8-slim

python-3.8-slim

Dockerfile with python:3.8-slim

Dockerfile with python:3.7-slim

python-3.7-slim

Dockerfile with python:3.7-slim

Dockerfile compatible with python:2.7-slim

python-2.7-slim

Merge remote-tracking branch 'refs/remotes/tutumcloud/master'