title: How to run specific code after all tests are executed?
body: <p>I would like to run specific code after all the tests are executed using pytest</p>
  
  <p>for eg: I open up a database connection before any tests are executed. And I would like to close the connection after all the tests are executed.</p>
  
  <p>How can i achieve this with py.test? Is there a fixture or some thing that can do this?</p>