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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 full_block_key(self):
 """ Returns the "correct" usage key value with the run filled in. """

        if self.block_key.run is None:
            # pylint: disable=unexpected-keyword-arg, no-value-for-parameter
            return self.block_key.replace(course_key=self.course_key)
        return self.block_key