def _tan_repl_func(expr):
    if isinstance(expr, tan):
        return sin(*expr.args) / cos(*expr.args)
    elif not expr.args or expr.is_Derivative:
        return expr
Returns a dictionary from content ids to subtopic ids.
dataset/ETHPy150Open sympy/sympy/sympy/physics/mechanics/functions.py/_tan_repl_func--crossover with--dataset/ETHPy150Open dossier/dossier.web/dossier/web/label_folders.py/Folders.grouped_items