old_contents: import pytest
  import sys
  
  if __name__ == "__main__":
      sys.exit(pytest.main(["tests"]))
new_contents: import pytest
  import sys
  
  if __name__ == "__main__":
      sys.exit(pytest.main(['--nbval-lax', '--cov=datascience', 'tests']))
subject: add coverage to python test run