(20241224) Get request array handling test.

models/api/finstitutions/trading/symbols/list.py

@@ -40,6 +40,7 @@ from pydantic import BaseModel, Field, field_validator, PastDatetime, model_vali
 from typing import Optional, Literal, Union, List
 
 # My utils:
+from utils_v2.string import json
 from utils_v2.string import regex
 from utils_v2.date_time import date_time
 
@@ -172,7 +173,12 @@ class TradingSymbolListRequestData(BaseModel):
 
     @field_validator("exchanges", mode = "before")
     def ensure_list(cls, value):
-        if not isinstance(value, list): value = [value]
+        _exchg = []
+        if isinstance(value, str):
+            if regex.match(text = value, pattern = r"\[.*\]"): _exchg = json.from_string(value)
+            else: _exchg.append(value)
+        elif isinstance(value, list):
+            _exchg = value
         return value