code: def __handle_variable(self, shell_entry, output):
          
          if 'variable' in shell_entry:
              variable_name = shell_entry['variable']
              self.pipeline.variables[variable_name] = "\n".join(output)
docs: Saving output for configured variable name.
  
          Args:
              shell_entry(dict): shell based configuration (shell, docker container or Python).
              output: list of strings representing output of last shell