Human-readable duration

human_duration.py

def human_duration(seconds):
  if seconds <= 1:
    return '0 seconds'
  units = (
      ('day', 86400),
      ('hour', 3600),
      ('minute', 60),
      ('second', 1),
  )
  parts = []
  for unit, duration in units:
    n = seconds // duration
    seconds %= duration
    if n:
      parts.append('%d %s' % (n, unit if n == 1 else unit + 's'))
  if len(parts) > 2:
    return '%s, and %s' % (', '.join(parts[:-1]), parts[-1])
  return ' and '.join(parts)