def min_sec(secs):
    """
    Takes an epoch timestamp and returns string of minutes:seconds.

    :param secs:
        Timestamp (in seconds)

    >>> import time
    >>> start = time.time()  # Wait a few seconds
    >>> finish = time.time()
    >>> min_sec(finish - start)
    '0:11'
    """
    secs = int(secs)
    return '%d:%02d' % (secs / 60, secs % 60)