This function computes the least common multiple (lcm) of
num1 and num2.
Parameters
num1
A GMP object, an int,
or a string that can be interpreted as a number following the same logic
as if the string was used in gmp_init() with automatic
base detection (i.e. when base is equal to 0).
num2
A GMP object, an int,
or a string that can be interpreted as a number following the same logic
as if the string was used in gmp_init() with automatic
base detection (i.e. when base is equal to 0).