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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 _is_shadowed(self, reaction_id, database):
 """Whether reaction in database is shadowed by another database"""

        for other_database in self._databases:
            if other_database == database:
                break
            if other_database.has_reaction(reaction_id):
                return True
        return False