import time


def process_rate(num_seqs, stime):
    """
    Calculate amount of time to process sequences

    :param num_seqs: Number of sequences processed
    :type num_seqs: int
    :param stime: Start time in seconds (since the epoch)
    :type stime: float
    :return: Number of sequences processed per second
    :rtype: float
    """
    etime = time.time()
    return num_seqs / (etime - stime)