fix tests and contrib: lazy import of torch_complex #192

	name: Tests

	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: [3.7, 3.8, 3.9, '3.10', '3.11']

	steps:
	- uses: actions/checkout@v3
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install linux dependencies
	run: \|
	sudo apt-get install libsndfile1
	- name: Install python dependencies
	run: \|
	python -m pip install --upgrade pip setuptools wheel
	pip install flake8 pytest pytest-cov codecov
	if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
	pip install numpy scipy Cython
	pip install --editable .[all]
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	#flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	#flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
	- name: Test with pytest
	run: \|
	pytest -v "tests/" "padertorch/"
	- name: Codecov
	run: \|
	codecov

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