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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 _sidConversion(cls, val, **kwargs):
        '''
        converts a list of pysid objects to string representations
        '''
        if isinstance(val, six.string_types):
            val = val.split(',')
        usernames = []
        for _sid in val:
            try:
                userSid = win32security.LookupAccountSid('', _sid)
                if userSid[1]:
                    userSid = '{1}\\{0}'.format(userSid[0], userSid[1])
                else:
                    userSid = '{0}'.format(userSid[0])
            # TODO: This needs to be more specific
            except Exception:
                userSid = win32security.ConvertSidToStringSid(_sid)
                log.warning('Unable to convert SID "%s" to a friendly name.  The SID will be disaplayed instead of a user/group name.', userSid)
            usernames.append(userSid)
        return usernames