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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 taropen(cls, name, mode="r", fileobj=None, **kwargs):
 """Open uncompressed tar archive name for reading or writing. """

        if len(mode) > 1 or mode not in "raw":
            raise ValueError("mode must be 'r', 'a' or 'w'")
        return cls(name, mode, fileobj, **kwargs)