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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(config, section, opt, value):
 """Sets specified option in the config. Args: config (configobj.ConfigObj):
 config to work on. section (str):
 section name. opt (str):
 option name. value: value to set option to. """

        if section not in config.keys():
            config[section] = {}

        config[section][opt] = value