def duration_string_format(delta):
    """ Pass me an integer and get a nice string with the corresponding duration """
    minutes, seconds = divmod(delta, 60)
    hours, minutes = divmod(minutes, 60)
    days, hours = divmod(hours, 24)
    ds = '' if (days == 1) else 's'
    hs = '' if (hours == 1) else 's'
    ms = '' if (minutes == 1) else 's'
    fdays = '' if (days == 0) else '{0} day{1}, '.format(days, ds)
    fhours = '' if (hours == 0) else '{0} hour{1}, '.format(hours, hs)
    return '{0}{1}{2} minute{3}'.format(fdays, fhours, minutes, ms)