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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 ivorn_prefix_present(session, ivorn_prefix):
 """ Predicate, returns whether there is an entry in the database with matching IVORN prefix. """

    n_matches = session.query(Voevent.ivorn).filter(
            Voevent.ivorn.like('{}%'.format(ivorn_prefix))).count()
    return bool(n_matches)