Kaba class Query ed

class Query
    var needs_step: bool
    var res: None
    var step_result: i32

    # constructors
    func mut __init__()

    # functions
    func column_names() -> string[]
    func mut get_column() -> Any?
    func mut get_column_text() -> string[]
    func mut has_more() -> bool
    func mut step()