📝 add documentation to create scope function

Author: ediskandarov-cur

mangum/adapter.py

@@ -100,12 +100,20 @@ def __call__(self, event: dict, context: "LambdaContext") -> dict:
 
             scope = self._create_scope(event, context)
             http_cycle = HTTPCycle(scope, text_mime_types=self.text_mime_types)
-
             response = http_cycle(self.app, initial_body)
 
         return response
 
     def _create_scope(self, event: dict, context: "LambdaContext") -> Scope:
+        """Creates a scope object according to ASGI specification from a Lambda Event.
+
+        https://asgi.readthedocs.io/en/latest/specs/www.html#http-connection-scope
+
+        The event comes from various sources: AWS ALB, AWS API Gateway of different
+        versions and configurations(multivalue header, etc).
+        Thus, some heuristics is applied to guess an event type.
+
+        """
         request_context = event["requestContext"]
 
         if event.get("multiValueHeaders"):