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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 fetch(args: List[str], env: Dict[str, str] = None, encoding: str = sys.getdefaultencoding()) -> str: """ Run a command and returns its stdout. Args: args: the command-line arguments env: the operating system environment to use encoding: the encoding to use for ``stdout`` Returns: the command's ``stdout`` output """

    stdout, _ = run(args, env=env, capture_stdout=True,
                    echo_stdout=False, encoding=encoding)
    log.debug(stdout)
    return stdout