docs: 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)