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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_4_yes_no(question):
 """ Ask a question and prompt for yes or no :param question: Question to ask; answer is yes/no :return: :boolean """

    while True:
        sys.stdout.write(question + ' (y/n)? ')
        try:
            choice = raw_input().lower()
        except:
            choice = input().lower()
        if choice == 'yes' or choice == 'y':
            return True
        elif choice == 'no' or choice == 'n':
            return False
        else:
            printError('\'%s\' is not a valid answer. Enter \'yes\'(y) or \'no\'(n).' % choice)