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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 encode(self, s):
 """Transform a string with a filename into a list of RGB integers. Args: s: path to the file with an image. Returns: ids: list of integers """

    try:
      import matplotlib.image as im  # pylint: disable=g-import-not-at-top
    except ImportError as e:
      tf.logging.warning(
          "Reading an image requires matplotlib to be installed: %s", e)
      raise NotImplementedError("Image reading not implemented.")
    return im.imread(s)