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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_section(self, name, create=True):
 """Retrieve a section by name. Create it on first access."""

        try:
            return self.sections[name]
        except KeyError:
            if not create:
                raise

            section = Section(name)
            self.sections[name] = section
            return section