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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 proxy_schema(self, value):
 """ Set the Proxy-Schema option of a request. :param value: the Proxy-Schema value """

        option = Option()
        option.number = defines.OptionRegistry.PROXY_SCHEME.number
        option.value = str(value)
        self.add_option(option)