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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_backend(self, backend_node):
 """parse `backend` sections Args: backend_node (TreeNode):
 Description Returns: config.Backend: an object """

        proxy_name = backend_node.backend_header.proxy_name.text
        config_block_lines = self.__build_config_block(
            backend_node.config_block)
        return config.Backend(name=proxy_name, config_block=config_block_lines)