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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 cache_git_tag():
 """ Try to read the current version from git and, if read successfully, cache it into the version cache file. If the git folder doesn't exist or if git isn't installed, this is a no-op. I.E. it won't blank out a pre-existing version cache file upon failure. :return: Project version string """

    try:
        version = __get_git_tag()
        with __open_cache_file('w') as vf:
            vf.write(version)
    except Exception:
        version = __default_version__
    return version