title: How can I manually trigger re-execution of a shared py.test fixture?
body: <p>Say I have a fixture which I want to share for most of my tests:</p>
  
  <pre><code>@pytest.fixture(scope='session')
  def account():
     # create a new account
  </code></pre>
  
  <p>But now in one of the tests, I want to override the <code>scope='session'</code> bit and actually have the fixture re-execute (create a new account). Is there a way to tell the fixture to "override the cache/memoization" just for one test?</p>