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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 _migration_required(connection):
 """ Returns True if ambry models do not match to db tables. Otherwise returns False. """

    stored_version = get_stored_version(connection)
    actual_version = SCHEMA_VERSION
    assert isinstance(stored_version, int)
    assert isinstance(actual_version, int)
    assert stored_version <= actual_version, \
        'Db version can not be greater than models version. Update your source code.'
    return stored_version < actual_version