use BeforeValidator for country codes

Author: giancarloromeo

packages/settings-library/src/settings_library/twilio.py

@@ -8,13 +8,16 @@
 
 from typing import Annotated, TypeAlias
 
-from pydantic import Field, StringConstraints, TypeAdapter, field_validator
+from pydantic import BeforeValidator, Field, StringConstraints, TypeAdapter
 
 from .base import BaseCustomSettings
 
-
 # Based on https://countrycode.org/
-CountryCodeStr: TypeAlias = Annotated[str, StringConstraints(strip_whitespace=True, pattern=r"^\d{1,4}")]
+CountryCodeStr: TypeAlias = Annotated[
+    str,
+    BeforeValidator(str),
+    StringConstraints(strip_whitespace=True, pattern=r"^\d{1,4}"),
+]
 
 
 class TwilioSettings(BaseCustomSettings):
@@ -30,13 +33,6 @@ class TwilioSettings(BaseCustomSettings):
         "See https://support.twilio.com/hc/en-us/articles/223133767-International-support-for-Alphanumeric-Sender-ID",
     )
 
-
-    @field_validator("TWILIO_COUNTRY_CODES_W_ALPHANUMERIC_SID_SUPPORT", mode="before")
-    @classmethod
-    def _parse_country_codes_from_env(cls, v):
-        return [str(cc) for cc in v]
-
-
     def is_alphanumeric_supported(self, phone_number: str) -> bool:
         # Some countries do not support alphanumeric serder ID
         #