Returns number of seconds elapsed since epoch
  Note that no timezone are taken into consideration.
  utc tuple must be: (year, month, day, hour, minute, second)

def utc_mktime(utc_tuple):
  """Returns number of seconds elapsed since epoch
  Note that no timezone are taken into consideration.
  utc tuple must be: (year, month, day, hour, minute, second)
  """
  if len(utc_tuple) == 6:
      utc_tuple += (0, 0, 0)
  return time.mktime(utc_tuple) - time.mktime((1970, 1, 1, 0, 0, 0, 0, 0, 0))