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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 fix_lockfile(self):
 """Run each line of outfile through fix_pin"""

        with open(self.outfile, 'rt') as fp:
            lines = [
                self.fix_pin(line)
                for line in self.concatenated(fp)
            ]
        with open(self.outfile, 'wt') as fp:
            fp.writelines([
                line + '\n'
                for line in lines
                if line is not None
            ])