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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 prompt_protocol():
 """ Prompt user if they would like to save pickle file as a dictionary or an object. :return str: Answer """

    stop = 3
    ans = ""
    while True and stop > 0:
        ans = input("Save as (d)ictionary or (o)bject?\n"
                    "* Note:\n"
                    "Dictionaries are more basic, and are compatible with Python v2.7+.\n"
                    "Objects are more complex, and are only compatible with v3.4+ ")
        if ans not in ("d", "o"):
            print("Invalid response: Please choose 'd' or 'o'")
        else:
            break
    # if a valid answer isn't captured, default to dictionary (safer, broader)
    if ans == "":
        ans = "d"
    return ans