---

The pytest framework makes it easy to write small tests, yet scales to support complex functional testing for applications and libraries.

An example of a simple test:

# content of test_sample.py
def inc(x):
    return x + 1

def test_answer():
    assert inc(3) == 5

To execute it:

$ pytest
============================= test session starts =============================
collected 1 items

test_sample.py F

================================== FAILURES ===================================
_________________________________ test_answer _________________________________

    def test_answer():
>       assert inc(3) == 5
E       assert 4 == 5
E        +  where 4 = inc(3)

test_sample.py:5: AssertionError
========================== 1 failed in 0.04 seconds ===========================

Due to pytest's detailed assertion introspection, only plain assert statements are used. See getting-started for more examples.