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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_answer_for_student(student_item, vote, rationale):
 """ Add an answer for a student to the backend Args: student_item (dict):
 The location of the problem this submission is associated with, as defined by a course, student, and item. vote (int):
 the option that student voted for rationale (str):
 the reason why the student vote for the option """

    answers = get_answers_for_student(student_item)
    answers.add_answer(vote, rationale)

    sub_api.create_submission(student_item, {
        ANSWER_LIST_KEY: answers.get_answers_as_list()
    })