get list of values from preset string

robot.py

@@ -54,6 +54,15 @@ class Robot:
             return self.angle != values
         return self.angle != self.target
 
+    @staticmethod
+    def read_preset(str):
+        if str.startswith('{') and str.endswith('}'):
+            str = str.lstrip('{').rstrip('}')
+        else:
+            return None     # malformed packet
+        data = str.split(',')
+        return [int(val) for val in data]
+
     def serial_read_handler(self, data):
         data = data.strip()
         if data.startswith(b'{') and data.endswith(b'}'):