```python
def setup():
a = py5.PI
c = py5.cos(a)
a_c = py5.acos(c)
# prints "3.1415927 : -1.0 : 3.14159261"
py5.println(round(a, 8), ':', round(c, 8), ':', round(a_c, 8))
```
```python
def setup():
a = py5.PI + py5.PI/4
c = py5.cos(a)
a_c = py5.acos(c)
# prints "3.92699087 : -0.70710674 : 2.35619443"
py5.println(round(a, 8), ':', round(c, 8), ':', round(a_c, 8))
```