name = input('Insert the name of a molecule/atom to find its RMM/RAM: ')
test = re.findall('([A-z][a-z]*)(\\d*)', name)
final = re.findall('[A-Z][a-z]*', ''.join([(a * int(b) if len(b) > 0 else a
    ) for a, b in test]))
Multiply an integer in a list by a word in the list