numbers module provides complex numbers and fractional numbers.
Once useComplex() is called, the suffix "i" of a number creates a complex number.
useComplex() a = 1 + 3i b = 3 - 4i a * b => (15+5i)
fraction() creates an Number object that represents a fractional number.
a = fraction(1, 2) => 1/2 b = fraction(4, 3) => 4/3 a + b => 11/6
gcd() returns a greatest common denomiator of the specified two integers. lcm() returns a lowest common multiple of the specified two integers.
gcd(6,9) => 3