get_avg_successRate(person) is nonsensical

[RyanO-K]

Currently, get_avg_successRate returns 'curr_avg / len(photos)'. Curr_avg is a float given by the summation of all the photos success rates. However the photo success rates always sum to 1, so avg_successRate is just 1 / the number of photos a person has. As it stands this is useless and should be discarded, unless I am missing something.