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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_cached_filename(self, filename, extention, settings_list=None):
 """Creates a filename with md5 cache string based on settings list Args: filename (str):
 the filename without extention extention (str):
 the file extention without dot. (i.e. 'pkl') settings_list (dict|list):
 the settings list as list (optional) NB! The dictionaries have to be sorted or hash id will change arbitrarely. """

        cached_name = "_".join([filename, self.get_hash()])
        return ".".join([cached_name, extention])