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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 _proc_builtin(self, tarfile):
 """Process a builtin type or an unknown type which will be treated as a regular file. """

        self.offset_data = tarfile.fileobj.tell()
        offset = self.offset_data
        if self.isreg() or self.type not in SUPPORTED_TYPES:
            # Skip the following data blocks.
            offset += self._block(self.size)
        tarfile.offset = offset

        # Patch the TarInfo object with saved global
        # header information.
        self._apply_pax_info(tarfile.pax_headers, tarfile.encoding, tarfile.errors)

        return self