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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 build_defaults(self, defaults_node):
 """parse `defaults` sections, and return a config.Defaults Args: defaults_node (TreeNode):
 Description Returns: config.Defaults: an object """

        proxy_name = defaults_node.defaults_header.proxy_name.text
        config_block_lines = self.__build_config_block(
            defaults_node.config_block)
        return config.Defaults(
            name=proxy_name,
            config_block=config_block_lines)