def _param_populator(self, src, t_offset=0):
        def getter(m, y, x, t):
            if isinstance(src[y], pd.core.frame.DataFrame):
                return float(src[y].loc[t + t_offset, x])
            else:
                return float(src[y])
        return getter
Returns a `getter` function that returns either
dataset/ETHPy150Open calliope-project/calliope/calliope/core.py/Model._param_populator