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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 read_yaml_file(self, file_name):
 """ Parses a YAML file into a matrix. :param file_name: name of the YAML file :return: a matrix with the file's contents """

        with open(os.path.join(self.__path(), os.path.basename(file_name)),
                  'rt') as yamlfile:
            return yaml.load(yamlfile)