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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 _get_param(self, section, key, config, default=None):
 """ Get configuration parameter "key" from config @str section: the section of the config file @str key: the key to get @dict config: the configuration (dictionnary) @str default: the default value if parameter "key" is not present @rtype: str (value of config['key'] if present default otherwith """

        if section in config and key in config[section]:
            return config[section][key]
        if default is not None:
            return default
        else:
            raise MissingParameter(section, key)