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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 create_ustar_header(self, info, encoding, errors):
 """Return the object as a ustar header block. """

        info["magic"] = POSIX_MAGIC

        if len(info["linkname"]) > LENGTH_LINK:
            raise ValueError("linkname is too long")

        if len(info["name"]) > LENGTH_NAME:
            info["prefix"], info["name"] = self._posix_split_name(info["name"])

        return self._create_header(info, USTAR_FORMAT, encoding, errors)