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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_params(self, arg_params, aux_params, allow_extra=False):
 """Assign, i.e. copy parameters to all the executors. Parameters arg_params : dict A dictionary of name to `NDArray` parameter mapping. aux_params : dict A dictionary of name to `NDArray` auxiliary variable mapping. allow_extra : boolean, optional Whether allow extra parameters that are not needed by symbol. If this is True, no error will be thrown when arg_params or aux_params contain extra parameters that is not needed by the executor. """

        for exec_ in self.execs:
            exec_.copy_params_from(arg_params, aux_params, allow_extra_params=allow_extra)