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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_open_filenames(self):

 """
 Set the recent opened files on editor based on active project.
 
 If no project is active, then editor filenames are saved, otherwise
 the opened filenames are stored in the project config info.
 """

        if self.projects is not None:
            if not self.projects.get_active_project():
                filenames = self.get_open_filenames()
                self.set_option('filenames', filenames)