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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 convert(self, path, version, target):
 """Converts the specified source file to a new version number."""

        source = self.comparer.get_representation(path)
        lines = [ '# <fortpy version="{}"></fortpy>\n'.format(version) ]

        for line in self.comparer.template.contents[version].preamble:
            lines.append(line.write(source.preamble, source.version, source.stored) + "\n")

        for line in self.comparer.template.contents[version].body:
            for valueset in source.body:
                lines.append(line.write(valueset, source.version, source.stored) + "\n")

        with open(os.path.expanduser(target), 'w') as f:
            f.writelines(lines)