def sanity_function(fn):
    "Mark a function as the test's sanity function.\n\n            Decorated functions must be unary and they will be converted into\n            deferred expressions.\n            "
    _def_fn = deferrable(fn)
    setattr(_def_fn, '_rfm_sanity_fn', True)
    return _def_fn
Mark a function as the test's sanity function.

Decorated functions must be unary and they will be converted into
deferred expressions.
def sanity_function(fn):
    "Mark a function as the test's sanity function.\n\n            Decorated functions must be unary and they will be converted into\n            deferred expressions.\n            "
    _def_fn = deferrable(fn)
    setattr(_def_fn, '_rfm_sanity_fn', True)
    return _def_fn