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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 input_option(message, options="yn", error_message=None):
 """ Reads an option from the screen, with a specified prompt. Keeps asking until a valid option is sent by the user. """

    def _valid(character):
        if character not in options:
            print(error_message % character)
    return input("%s [%s]" % (message, options), _valid, True, lambda a: a.lower())