class_docstr: used for short urls
code: def _validate_explore_url(url: str) -> Optional[str]:
      if url.startswith("//superset/explore/p/"):
          return url
  
      if url.startswith("//superset/explore"):
          return (
              "/" + url[10:]
          )  # Remove /superset from old Explore URLs
  
      if url.startswith("//explore"):
          return url
  
      return None
  
file_path: superset/superset/views/redirects.py
imports: import logging
  from typing import Optional
  from flask import flash
  from flask_appbuilder import expose
  from werkzeug.utils import redirect
  from superset import db, event_logger
  from superset.models import core
  from superset.superset_typing import FlaskResponse
  from superset.views.base import BaseSupersetView
label_desc: Use image node_id 1 for calling the R obj's underlying member method code with example usage: obj._validate_explore_url(url) and returns: None, url, unknown, url