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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_subprocess_output(cls, command, ignore_stderr=True, **kwargs):
 """Get the output of an executed command. :param command: An iterable representing the command to execute (e.g. ['ls', '-al']). :param ignore_stderr: Whether or not to ignore stderr output vs interleave it with stdout. :raises: `ProcessManager.ExecutionError` on `OSError` or `CalledProcessError`. :returns: The output of the command. """

    if ignore_stderr is False:
      kwargs.setdefault('stderr', subprocess.STDOUT)

    try:
      return subprocess.check_output(command, **kwargs).decode('utf-8').strip()
    except (OSError, subprocess.CalledProcessError) as e:
      subprocess_output = getattr(e, 'output', '').strip()
      raise cls.ExecutionError(str(e), subprocess_output)