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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 _add_ideal_weight_percent_(elemental_array):
 """ Adds the "weight_percent" property to each of the dictionaries in elemental_array :param elemental_array: an array of dictionaries containing information about the elements in the system :return: the appended elemental_array """

    t_mass = _calculate_total_mass_(elemental_array)
    for a in elemental_array:
        a["weight_percent"] = a["weight"] / t_mass * 100
    return elemental_array