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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 config_to_string(config):
 """Nice output string for the config, which is a nested defaultdict. Args: config (defaultdict(defaultdict)):
 The configuration information. Returns: str: A human-readable output string detailing the contents of the config. """

    output = []
    for section, section_content in config.items():
        output.append("[{}]".format(section))
        for option, option_value in section_content.items():
            output.append("{} = {}".format(option, option_value))
    return "\n".join(output)