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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 _ensure_dir(self, template_name):
 """Ensure the output directory for a template exists."""

        head = os.path.dirname(template_name)
        if head:
            file_dirpath = os.path.join(self.outpath, head)
            if not os.path.exists(file_dirpath):
                os.makedirs(file_dirpath)