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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 check_version_info(conn, version_table, expected_version):
 """ Checks for a version value in the version table. Parameters conn : sa.Connection The connection to use to perform the check. version_table : sa.Table The version table of the asset database expected_version : int The expected version of the asset database Raises ------ AssetDBVersionError If the version is in the table and not equal to ASSET_DB_VERSION. """


    # Read the version out of the table
    version_from_table = conn.execute(
        sa.select((version_table.c.version,)),
    ).scalar()

    # A db without a version is considered v0
    if version_from_table is None:
        version_from_table = 0

    # Raise an error if the versions do not match
    if (version_from_table != expected_version):
        raise AssetDBVersionError(db_version=version_from_table,
                                  expected_version=expected_version)