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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 handleHeader(self, key, value):
        "extends handleHeader to save headers to a local response object"
        key_lower = key.lower()
        if key_lower == 'location':
            value = self.modLocationPort(value)
        self._response.headers[key_lower] = value
        if key_lower != 'cache-control':
            # This causes us to not pass on the 'cache-control' parameter
            # to the browser
            # TODO: we should have a means of giving the user the option to
            # configure how they want to manage browser-side cache control
            proxy.ProxyClient.handleHeader(self, key, value)