def __init__(self, key=None, **kwargs):
    if not key:
      raise ValueError(u'Missing key.')

    super(RC4Decrypter, self).__init__()
    self._rc4_cipher = ARC4.new(key)
Performs operations to clean things up after performing diagnostics.
dataset/ETHPy150Open log2timeline/dfvfs/dfvfs/encryption/rc4_decrypter.py/RC4Decrypter.__init__--crossover with--dataset/ETHPy150Open GoogleCloudPlatform/gsutil/gslib/commands/perfdiag.py/PerfDiagCommand._TearDown