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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 file_or_stdin() -> Callable: """ Returns a file descriptor from stdin or opening a file from a given path. """


    def parse(path):
        if path is None or path == "-":
            return sys.stdin
        else:
            return data_io.smart_open(path)

    return parse