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.

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