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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 get_file(self, filename):
 """Get a file from the repo. Returns a file-like stream with the data. """

        log.debug('[%s]: reading: //%s/%s', self.name, self.name, filename)
        try:
            blob = self.repo.head.commit.tree/filename
            return blob.data_stream
        except KeyError as err:
            raise GitError(err)