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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 value(self):
 """Returns the value of this Slot."""

    if hasattr(self, '_value_decoded'):
      return self._value_decoded

    if self.value_blob is not None:
      encoded_value = self.value_blob.open().read()
    else:
      encoded_value = self.value_text

    self._value_decoded = json.loads(encoded_value, cls=util.JsonDecoder)
    return self._value_decoded