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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 _set_cached_value(self, xblock, value):
 """Store a value in the xblock's cache, creating the cache if necessary."""

        # pylint: disable=protected-access
        if not hasattr(xblock, '_field_data_cache'):
            xblock._field_data_cache = {}
        xblock._field_data_cache[self.name] = value