def _exists(sym, _larch=None):
    return which(sym, _larch=_larch, **kws) is not None
Runs all set type transformers / validators against the provided input parameters and returns any errors
dataset/ETHPy150Open xraypy/xraylarch/lib/builtins.py/_exists--crossover with--dataset/ETHPy150Open timothycrosley/hug/hug/interface.py/Interface.validate