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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 update(self, content=None):
 """ Update values based on the requested content Parameters content Returns ------- """

        if not content:
            return
        if content == 'summary' or 'extended' or 'powerflow':
            self._update_summary(self.system)
        if content == 'extended' or 'powerflow':
            self._update_extended(self.system)