import tensorflow as tf

      unicode strings
    """
    chars_total = 0
    for fname in filepaths:
      chars_this_file = 0
      tf.logging.info("reading file %s" % fname)
      for text in self.filepath_to_unicode_strings(fname):
        if (max_chars_per_file and
            chars_this_file + len(text) > max_chars_per_file):
          text = text[:max_chars_per_file - chars_this_file]
