>>> from funcio import calculem


>>> r=round(calculem(1), 1)
>>> r
0.4
>>> r=round(calculem(2), 1)
>>> r
1.3
>>> r=round(calculem(0), 1)
>>> r
0.0
>>> r=round(calculem(10), 1)
>>> r
1.7
>>> r=round(calculem(20), 1)
>>> r
3.3