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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 update_config(self, config_dict, config_file):
 """Update the content and reference of the config :param dict config_dict: The new configuration :param str config_file: The new file reference """

        config_path = path.dirname(config_file)
        self.config.config_file_path = config_file
        self.config.path = config_path
        for config_key, config_value in config_dict.items():
            if config_value != self.config.get_config_value(config_key):
                self.set_preliminary_config_value(config_key, config_value)