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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 write(self):
 """ Writes the ``.sln`` file to disk. """

        filters = {
            'MSGUID': lambda x: ('{%s}' % x).upper(),
            'relslnfile': lambda x: os.path.relpath(x, os.path.dirname(self.FileName))
        }
        context = {
            'sln': self
        }
        return self.render(self.__jinja_template__, self.FileName, context, filters)