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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 delete_commit(self, commit):
 """ Deletes a commit. Params: * commit: A tuple, string, or Commit object representing the commit. """

        req = proto.DeleteCommitRequest(commit=commit_from(commit))
        self.stub.DeleteCommit(req, metadata=self.metadata)