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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _CurrentAuditLog():
 """Get the rdfurn of the current audit log."""

  now_sec = rdfvalue.RDFDatetime.Now().AsSecondsSinceEpoch()
  rollover_seconds = AUDIT_ROLLOVER_TIME.seconds
  # This gives us a filename that only changes every
  # AUDIT_ROLLOVER_TIfilME seconds, but is still a valid timestamp.
  current_log = (now_sec // rollover_seconds) * rollover_seconds
  return _AuditLogBase().Add(str(current_log))