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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 create_cache_directories(self):
 """Ensure that SourceProcessor cache directories exist."""

        if not os.path.isdir(self.package_cache_dir):
            if not os.path.isdir(self.stacker_cache_dir):
                os.mkdir(self.stacker_cache_dir)
            os.mkdir(self.package_cache_dir)