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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 set_value(self, attribute, section, value):
 """ Sets requested attribute value. Usage:: "[Section B]\\n", "Attribute 2 = \\"Value B\\"\\n"] <foundations.parsers.SectionsFileParser object at 0x109304209> True :param attribute: Attribute name. :type attribute: unicode :param section: Section containing the searched attribute. :type section: unicode :param value: Attribute value. :type value: object :return: Definition success. :rtype: bool """


        if not self.section_exists(section):
            LOGGER.debug("> Adding '{0}' section.".format(section))
            self.__sections[section] = OrderedDict() if self.__preserve_order else dict()

        self.__sections[section][attribute] = value

        return True