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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 _parse_header_code(self):
 """Extract header information and PDB code."""

        code, header = '', ''
        if 'OTHERS' in self.df:

            header = (self.df['OTHERS'][self.df['OTHERS']['record_name'] ==
                      'HEADER'])
            if not header.empty:
                header = header['entry'].values[0]
                s = header.split()
                if s:
                    code = s[-1].lower()
        return header, code