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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 prepare(value, should_escape):
 """ Prepares a value to be added to the result :param value: The value to add to the result :param should_escape: If the string should be HTML-escaped :return: A unicode string or strlist """


    if value is None:
        return u''
    type_ = type(value)
    if type_ is not strlist:
        if type_ is not str_class:
            if type_ is bool:
                value = u'true' if value else u'false'
            else:
                value = str_class(value)
        if should_escape:
            value = escape(value)
    return value