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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 _del_cached_value(self, xblock):
 """Remove a value from the xblock's cache, if the cache exists."""

        # pylint: disable=protected-access
        if hasattr(xblock, '_field_data_cache') and self.name in xblock._field_data_cache:
            del xblock._field_data_cache[self.name]