def inc(a):
    return a + 1

def is_odd(a):
    return (1&a == 1)

def clean_str(a):
    return a.strip()

def test_func1():
    assert inc(0)==1
    assert inc(1)==2
    assert inc(5)==6
def test_func2():
    assert is_odd(1)==True
    assert is_odd(3)==True
def test_func3():
    assert clean_str("hello world  ")=="hello world  ".strip()


