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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 set_secure(self, section, option, value):
 """Set an option and mark it as secure. Any subsequent uses of 'set' or 'get' will also now know that this option is secure as well. """

        if self.keyring_available:
            s_option = "%s%s" % (section, option)
            self._unsaved[s_option] = ('set', value)
            value = self._secure_placeholder
        ConfigParser.set(self, section, option, value)