<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def is_affirmative(self, section, option):
 """ Return true if the section option combo exists and it is set to a truthy value. """

        return self.has_option(section, option) and \
            lib.is_affirmative(self.get(section, option))