Py.test Fixture error

gistfile1.py

import pytest

def setup_function(function):
    foo = 1
    function(foo)

def test_thing(thing):
    two = thing + 1
    assert two == 2

gistfile2.sh

(.env)Robs-MacBook-Pro:tests robstory$ py.test fixtures.py
====================================================================================================== test session starts =======================================================================================================
platform darwin -- Python 2.7.9 -- py-1.4.26 -- pytest-2.6.4
collected 1 items 

fixtures.py E

============================================================================================================= ERRORS =============================================================================================================
__________________________________________________________________________________________________ ERROR at setup of test_thing __________________________________________________________________________________________________
file /Users/robstory/simple/data101/tests/fixtures.py, line 7
  def test_thing(thing):
        fixture 'thing' not found
        available fixtures: pytestconfig, recwarn, monkeypatch, capfd, capsys, tmpdir
        use 'py.test --fixtures [testpath]' for help on them.

/Users/robstory/simple/data101/tests/fixtures.py:7
==================================================================================================== 1 error in 0.01 seconds =====================================================================================================
(.env)Robs-MacBook-Pro:tests robstory$ 

import pytest

@pytest.fixture
def thing():
    return 1

def test_thing(thing):
    two = thing + 1
    assert two == 2