Write a Python function for scoring a sequence alignment. The
function would be defined as

def score(aligned_seq1, aligned_seq2, m, mm, g):

where aligned_seq1 and aligned_seq2 are aligned strings, m is the match
cost such as 10, mm is the mismatch cost such as 2, and g is the
gap cost such as -2. 

Submit a hardcopy in class on Feb 8th.