Update code based on limitations of python 3.9. `http.HTTPMethod` and `typing.override` are not available.

nucypher/policy/conditions/json/api.py

@@ -1,11 +1,15 @@
-from http import HTTPMethod
-from typing import Any, Optional, Tuple, override
+from typing import Any, Optional, Tuple
 
 from marshmallow import ValidationError, fields, post_load, validate, validates
 from marshmallow.fields import Url
+from typing_extensions import override
 
 from nucypher.policy.conditions.context import is_context_variable
-from nucypher.policy.conditions.json.base import JSONPathField, JsonRequestCall
+from nucypher.policy.conditions.json.base import (
+    HTTPMethod,
+    JSONPathField,
+    JsonRequestCall,
+)
 from nucypher.policy.conditions.json.utils import process_result_for_condition_eval
 from nucypher.policy.conditions.lingo import (
     ConditionType,

nucypher/policy/conditions/json/base.py

@@ -1,6 +1,7 @@
 import json
 from abc import ABC
-from http import HTTPMethod, HTTPStatus
+from enum import Enum
+from http import HTTPStatus
 from typing import Any, Optional
 
 import requests
@@ -17,6 +18,11 @@ from nucypher.policy.conditions.exceptions import JsonRequestException
 from nucypher.utilities.logging import Logger
 
 
+class HTTPMethod(Enum):
+    GET = "GET"
+    POST = "POST"
+
+
 class JsonRequestCall(ExecutionCall, ABC):
     TIMEOUT = 5  # seconds
 
@@ -62,15 +68,14 @@ class JsonRequestCall(ExecutionCall, ABC):
                     timeout=self.timeout,
                     headers=headers,
                 )
-            elif self.http_method == HTTPMethod.POST:
+            else:
+                # POST
                 response = requests.post(
                     resolved_endpoint,
                     data=json.dumps(resolved_parameters),
                     timeout=self.timeout,
                     headers=headers,
                 )
-            else:
-                raise RuntimeError(f"Unsupported http method: {self.http_method}")
 
             response.raise_for_status()
             if response.status_code != HTTPStatus.OK:

nucypher/policy/conditions/json/rpc.py

@@ -1,15 +1,19 @@
 from abc import ABC
-from http import HTTPMethod
-from typing import Any, Optional, Tuple, override
+from typing import Any, Optional, Tuple
 
 from marshmallow import ValidationError, fields, post_load, validate, validates
 from marshmallow.fields import Url
+from typing_extensions import override
 
 from nucypher.policy.conditions.context import is_context_variable
 from nucypher.policy.conditions.exceptions import (
     JsonRequestException,
 )
-from nucypher.policy.conditions.json.base import JSONPathField, JsonRequestCall
+from nucypher.policy.conditions.json.base import (
+    HTTPMethod,
+    JSONPathField,
+    JsonRequestCall,
+)
 from nucypher.policy.conditions.json.utils import process_result_for_condition_eval
 from nucypher.policy.conditions.lingo import (
     ConditionType,