title: pytest fixtures Redefining name from outer scope [pylint]
body: <p>I'm learning pytest and I lint my code with pylint.
  But pylint still complaints about:<br>
  <code>W0621: Redefining name %r from outer scope (line %s)</code></p>
  
  <p>for the following example from pytest:</p>
  
  <pre><code># test_wallet.py
  
  @pytest.fixture
  def my_wallet():
      '''Returns a Wallet instance with a zero balance'''
      return Wallet()
  
  @pytest.mark.parametrize("earned,spent,expected", [
      (30, 10, 20),
      (20, 2, 18),
  ])
  def test_transactions(my_wallet, earned, spent, expected):
      my_wallet.add_cash(earned)
      my_wallet.spend_cash(spent)
      assert my_wallet.balance == expected
  </code></pre>
  
  <p>Redefining name <code>my_wallet</code> from outer scope.</p>
  
  <p>I found workaround to add <code>_</code> prefix to the fixture name: <code>_my_wallet</code>.</p>
  
  <p>What would be the best practice if I want to keep fixtures in same file as functions?  </p>
  
  <ol>
  <li>Prepend all fixtures with <code>_</code>?</li>
  <li>Disable this <code>pylint</code> check for tests?</li>
  <li>Better suggestion?</li>
  </ol>