-r requirements.txt
pytest==3.6.1
pytest-cov==2.5.1
wheel==0.31.1
matplotlib==2.2.2

-r requirements.txt
pytest==4.4.0
pytest-cov==2.5.1
wheel==0.31.1
matplotlib==2.2.2

Update pytest from 3.6.1 to 4.4.0
Update pytest from 3.6.1 to 4.4.0