Update keras example #1569

	name: "code checks"

	on: push

	jobs:
	code-checks:
	runs-on: ubuntu-20.04
	steps:
	- name: checkout
	uses: actions/checkout@v3

	- name: init venv
	run: .devcontainer/bin/init_venv.sh

	- name: check Python imports
	run: >
	.venv/bin/isort . --check --diff
	--skip .venv
	--skip .mnist-keras
	--skip .mnist-pytorch
	--skip fedn_pb2.py
	--skip fedn_pb2_grpc.py

	- name: check Python formatting
	run: >
	.venv/bin/autopep8 --recursive --diff
	--exclude .venv
	--exclude .mnist-keras
	--exclude .mnist-pytorch
	--exclude fedn_pb2.py
	--exclude fedn_pb2_grpc.py
	.

	- name: run Python linter
	run: >
	.venv/bin/flake8 .
	--exclude ".venv,.mnist-keras,.mnist-pytorch,fedn_pb2.py,fedn_pb2_grpc.py"

	- name: check for floating imports
	run: >
	! grep -E -R
	--exclude-dir='.venv'
	--exclude-dir='.mnist-pytorch'
	--exclude-dir='.mnist-keras'
	--exclude-dir='docs'
	--exclude-dir='flower-client'
	--exclude='tests.py'
	'^[ \t]+(import\|from) ' -I .

	# TODO: add linting/formatting for all file types

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