'Return a Set of sys.modules filenames to monitor.'

def sysfiles(self):

    files = set()
    for (k, m) in sys.modules.items():
        if re.match(self.match, k):
            if (hasattr(m, '__loader__') and hasattr(m.__loader__, 'archive')):
                f = m.__loader__.archive
            else:
                f = getattr(m, '__file__', None)
                if ((f is not None) and (not os.path.isabs(f))):
                    f = os.path.normpath(os.path.join(_module__file__base, f))
            files.add(f)
    return files
