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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 log(self, _from=None, to=None):
 """Run git-log."""


        command = ["git", "log"]

        if _from:
            to = "HEAD" if not to else to
            revision_range = f"{_from}..{to}"
            command.append(revision_range)

        git_log_text = _run_command(command)
        commit_text_lst = _extract_commit_texts(git_log_text)

        return [Commit(commit_text) for commit_text in commit_text_lst]