import pytest

@pytest.mark.math
def test_one_plus_one():
    assert 1 + 1 == 2

@pytest.mark.math
def test_one_plus_two():
    a = 1
    b = 2
    c = 3
    assert a + b == c


def inc(x):
    return x + 1

@pytest.mark.math
def test_answer():
    assert inc(3) == 4


#handles exceptions
@pytest.mark.math
def test_divide_by_zero():
    with pytest.raises(ZeroDivisionError) as e:
        num = 1 / 0
    assert 'division by zero' in str(e.value)
