text: from __future__ import annotations
  
  from typing import Optional
  
  from pydantic import AnyUrl, BaseModel, conint
  
  
  class Problem(BaseModel):
      detail: Optional[str] = None
      instance: Optional[AnyUrl] = None
      status: Optional[conint(ge=100, lt=600)] = None
      title: Optional[str] = None
      type: Optional[AnyUrl] = 'about:blank'
  