code: def fkapply(models,pool,fn,missing_fn,(nombre,pkey,field),*args):
    "wrapper for do_* funcs to call process_* with missing handler. Unpacks the FieldKey."
    if (nombre,pkey) in models: return fn(pool,models[nombre,pkey],field,*args)
    else: return missing_fn(pool,field,*args) if missing_fn else ['missing'f fkapply(models,pool,fn,missing_fn,(nombre,pkey,field),*args):
    "wrapper for do_* funcs to call process_* with missing handler. Unpacks the FieldKey."
    if (nombre,pkey) in models: return fn(pool,models[nombre,pkey],field,*args)
    else: return missing_fn(pool,field,*args) if missing_fn else ['missing']
docs: wrapper for do_* funcs to call process_* with missing handler. Unpacks the FieldKey.