-r requirements.txt
pytest==4.1.1
pytest-mock==1.10.0
pytest-cov==2.6.1
pytest-xdist==1.26.1
requests-mock==1.5.2
freezegun==0.3.11
flake8==3.6.0
flake8-print==3.1.0

-r requirements.txt
pytest==4.1.1
pytest-mock==1.10.0
pytest-cov==2.6.1
pytest-xdist==1.26.1
requests-mock==1.5.2
freezegun==0.3.11
flake8==3.7.3
flake8-print==3.1.0

Update flake8 from 3.6.0 to 3.7.3
Update flake8 from 3.6.0 to 3.7.3