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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 abbreviate_sha1(cls, sha1):
 """Uniquely abbreviates the given SHA1."""


        # For now we invoke git-rev-parse(1), but hopefully eventually
        # we will be able to do this via pygit2.
        cmd = ['git', 'rev-parse', '--short', sha1]
        # cls.logger.debug(" ".join(cmd))
        out = subprocess.check_output(cmd, universal_newlines=True).strip()
        # cls.logger.debug(out)
        return out