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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 filepath_to_unicode_strings(self, filepath):
 """Read text out of an input file. The default just reads the text, converts to unicode and yields one unicode string. Subclasses can override this function in order to preprocess, and can yield any number of strings. Args: filepath: a string Yields: unicode strings. """

    f = tf.gfile.Open(filepath)
    b = f.read()
    yield text_encoder.to_unicode_ignore_errors(b)