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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(self, section, key, default=MANIFEST_NULL_KEY):
 """ Returns the value if it exist, or default if default is set """

        if not self.manifest.has_option(section, key) and default is not MANIFEST_NULL_KEY:
            return default
        return self.manifest.get(section, key)