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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(test_input = None):
 """ Prompt function that works for Python2 and Python3 :param test_input: Value to be returned when testing :return: Value typed by user (or passed in argument when testing) """

    if test_input != None:
        if type(test_input) == list and len(test_input):
            choice = test_input.pop(0)
        elif type(test_input) == list:
            choice = ''
        else:
            choice = test_input
    else:
        # Coverage: 4 missed statements
        try:
            choice = raw_input()
        except:
            choice = input()
    return choice