Call close() and join() on ParallelEvaluator's Pool object (this appears to be necessary to avoid memory leaks, see #22).

Author: CodeReclaimers

neat/parallel.py

@@ -12,6 +12,10 @@ def __init__(self, num_workers, eval_function, timeout=None):
         self.timeout = timeout
         self.pool = Pool(num_workers)
 
+    def __del__(self):
+        self.pool.close()
+        self.pool.join()
+
     def evaluate(self, genomes):
         jobs = []
         for genome in genomes: