<<< native
[ EStyled
    TextBoldScript
    [ EArray
        [ AlignLeft ]
        [ [ [ EText TextNormal "ABCDEFGHIJKLMNOPQRSTUVWXYZ" ] ]
        , [ [ EText TextNormal "abcdefghijklmnopqrstuvwxyz" ] ]
        ]
    ]
]
>>> tex
\mathcal{\begin{array}{l}
\text{ABCDEFGHIJKLMNOPQRSTUVWXYZ} \\
\text{abcdefghijklmnopqrstuvwxyz}
\end{array}}