<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _get_config_file_in_folder(cls, path):
 """Look for a configuration file in `path`. If exists return its full path, otherwise None. """

        if os.path.isfile(path):
            path = os.path.dirname(path)

        for fn in cls.PROJECT_CONFIG_FILES:
            config = RawConfigParser()
            full_path = os.path.join(path, fn)
            if config.read(full_path) and cls._get_section_name(config):
                return full_path