Reverse Roman Numerals
Created on Dec. 22, 2018 by Julien Palard
Write a function named from_roman_numeral
that return the value of a given roman numeral.
Example
>>> print(from_roman_numeral("V"))
5
>>> print(from_roman_numeral("XX"))
20
>>> print(from_roman_numeral("DCCC"))
800
>>> print(from_roman_numeral("MMMM"))
4000