num2words version 0.5.5 Mac OS X 10.12.6
from num2words import num2words
print(num2words(int(10), lang='ru')) # десять → 10
print(num2words(float(10), lang='ru')) # десять запятая ноль → 10.0
print(num2words(int(10))) # ten → 10
print(num2words(float(10))) # ten → 10
In Russian, it seems to express it when it becomes .0. In English, it seems that it is considered that there is no case of .0.