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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_git_version(cls):
 """ Return version of git current shell points to. If version cannot be parsed None is returned. @rtype: tuple or None """

        try:
            output = cls.run_git_shell('git version')
        except CalledProcessError:
            cls.LOG.warning("Unable to get Git version.")
            return None

        try:
            version = output.split()[2]
        except IndexError:
            cls.LOG.warning("Unable to parse Git version \"%s\".", output)
            return None

        try:
            return tuple(int(v) for v in version.split('.'))
        except ValueError:
            cls.LOG.warning("Unable to parse Git version \"%s\".", version)
            return None