Added improved models

src/cpl_reactive_extensions/abc/operator.py

@@ -0,0 +1,12 @@
+from abc import ABC
+from typing import Any
+
+from cpl_reactive_extensions.subscriber import Subscriber
+
+
+class Operator(ABC):
+    def __init__(self):
+        ABC.__init__(self)
+
+    def call(self, subscriber: Subscriber, source: Any):
+        pass