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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 user_choice(prompt, choices=("yes", "no"), default=None):
 """ Prompts the user for confirmation. The default value, if any, is capitalized. :param prompt: Information to display to the user. :param choices: an iterable of possible choices. :param default: default choice :return: the user's choice """

    assert default is None or default in choices
    choice_list = ', '.join((choice.title() if choice == default else choice for choice in choices))
    response = None
    while response not in choices:
        response = input(prompt + ' [' + choice_list + ']: ')
        response = response.lower() if response else default
    return response