@classmethod
def get_postmortem_debugger(cls, bits=None):
    """
        Returns the postmortem debugging settings from the Registry.

        @see: L{set_postmortem_debugger}

        @type  bits: int
        @param bits: Set to C{32} for the 32 bits debugger, or C{64} for the
            64 bits debugger. Set to {None} for the default (L{System.bits}.

        @rtype:  tuple( str, bool, int )
        @return: A tuple containing the command line string to the postmortem
            debugger, a boolean specifying if user interaction is allowed
            before attaching, and an integer specifying a user defined hotkey.
            Any member of the tuple may be C{None}.
            See L{set_postmortem_debugger} for more details.

        @raise WindowsError:
            Raises an exception on error.
        """
    if bits is None:
        bits = cls.bits
    elif bits not in (32, 64):
        raise NotImplementedError('Unknown architecture (%r bits)' % bits)
    if bits == 32 and cls.bits == 64:
        keyname = (
            'HKLM\\SOFTWARE\\Wow6432Node\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug'
            )
    else:
        keyname = (
            'HKLM\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug')
    key = cls.registry[keyname]
    debugger = key.get('Debugger')
    auto = key.get('Auto')
    hotkey = key.get('UserDebuggerHotkey')
    if auto is not None:
        auto = bool(auto)
    return debugger, auto, hotkey
