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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_version(cls, path, memo={}):
 """ Return a string describing the version of the repository at ``path`` if possible, otherwise throws ``subprocess.CalledProcessError``. (Note: memoizes the result in the ``memo`` parameter) """

        if path not in memo:
            memo[path] = subprocess.check_output(
                "git describe --tags --dirty 2> /dev/null",
                shell=True, cwd=path).strip().decode("utf-8")

            v = re.search("-[0-9]+-", memo[path])
            if v is not None:
                # Replace -n- with -branchname-n-
                branch = r"-{0}-\1-".format(cls.get_branch(path))
                (memo[path], _) = re.subn("-([0-9]+)-", branch, memo[path], 1)

        return memo[path]