def _fileUrandom(self, nbytes):
        """
        Wrapper around random file sources.

        This method isn't meant to be call out of the class and could be
        removed arbitrarily.
        """
        for src in self.randomSources:
            try:
                f = file(src, 'rb')
            except (__HOLE__, OSError):
                pass
            else:
                bytes = f.read(nbytes)
                f.close()
                return bytes
        raise SourceNotAvailable("File sources not available: %s" %
                                 (self.randomSources,))
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/python/randbytes.py/RandomFactory._fileUrandom