code: def is_valid_user(self, username, password):
      if username not in self.creds:
          return False
      hashed_pwd = hash_password(username, password)
      return self.creds[username].lower() == hashed_pwd.lower()
  
file_path: TabPy/tabpy/tabpy_server/handlers/basic_auth_server_middleware_factory.py
imports: import base64
  import secrets
  from pyarrow.flight import ServerMiddlewareFactory, ServerMiddleware
  from pyarrow.flight import FlightUnauthenticatedError
  from tabpy.tabpy_server.handlers.util import hash_password
label_desc: Use image node_id 2 for calling the BasicAuthServerMiddlewareFactory obj's underlying member method code with example usage: obj.is_valid_user(username, password) and returns: unknown, False