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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_sdk_dir(self):
 """Return the MSSSDK given the version string."""

        try:
            return self._sdk_dir
        except AttributeError:
            sdk_dir = self.find_sdk_dir()
            self._sdk_dir = sdk_dir
            return sdk_dir