<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def file_local_list(self, saltenv='base'):
        '''
        List files in the local minion files and localfiles caches
        '''
        filesdest = os.path.join(self.opts['cachedir'], 'files', saltenv)
        localfilesdest = os.path.join(self.opts['cachedir'], 'localfiles')

        fdest = self._file_local_list(filesdest)
        ldest = self._file_local_list(localfilesdest)
        return sorted(fdest.union(ldest))