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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 get_postmortem_exclusion_list(cls, bits = None):
 """ Returns the exclusion list for the postmortem debugger. @see: L{get_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: list( str ) @return: List of excluded application filenames. @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\\AutoExclusionList'
        else:
            keyname = 'HKLM\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\AeDebug\\AutoExclusionList'

        try:
            key = cls.registry[keyname]
        except KeyError:
            return []

        return [name for (name, enabled) in key.items() if enabled]