langchain.js
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    Operator:
        | "="
        | "!="
        | ">"
        | "<>"
        | "<"
        | ">="
        | "<="
        | "LIKE"
        | "NOT LIKE"
        | "IN"
        | "NOT IN"
        | "IS NULL"
        | "IS NOT NULL"

    Valid SQL operators that can be used in filter conditions