used _step_requires_iterator from _unit_utils and delete the version from _loop_utils #1740

	name: unit test

	on:
	push:
	branches: [ master ]
	pull_request:

	jobs:
	unit_tests:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: [3.8, 3.9]
	steps:
	- name: Check out repo
	uses: actions/checkout@v2
	- name: Setup conda env
	uses: conda-incubator/setup-miniconda@v2
	with:
	miniconda-version: "latest"
	activate-environment: test
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	shell: bash -l {0}
	run: \|
	set -eux
	conda activate test
	pip install -r requirements.txt
	pip install -r dev-requirements.txt
	pip install --no-build-isolation -e .
	conda install pytorch cpuonly -c pytorch-nightly
	- name: Run unit tests with coverage
	shell: bash -l {0}
	run: \|
	set -eux
	conda activate test
	pytest --cov=. --cov-report xml tests -vv
	- name: Upload Coverage to Codecov
	uses: codecov/codecov-action@v2

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