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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 _validate_assets(self, assets):
 """Validate that asset identifiers are contained in the daily bars. Parameters assets : array-like[int] The asset identifiers to validate. Raises ------ NoDataForSid If one or more of the provided asset identifiers are not contained in the daily bars. """

        missing_sids = np.setdiff1d(assets, self.sids)

        if len(missing_sids):
            raise NoDataForSid(
                'Assets not contained in daily pricing file: {}'.format(
                    missing_sids
                )
            )