code: def get_user_from_identifier(settings, identifier):
      
      providers = list(auth.strip() for auth in settings.get('authenticators').split(','))
      identities = Identity.find_all(Identity.provider.in_(providers), Identity.identifier == identifier)
      if identities:
          return sorted(identities, key=lambda x: providers.index(x.provider))[0].user
      for provider in providers:
          try:
              identity_info = multipass.get_identity(provider, identifier)
          except IdentityRetrievalFailed:
              continue
          if identity_info is None:
              continue
          if not identity_info.provider.settings.get('trusted_email'):
              continue
          emails = {email.lower() for email in identity_info.data.getlist('email') if email}
          if not emails:
              continue
          user = User.find_first(~User.is_deleted, User.all_emails.in_(list(emails)))
          if user:
              return user
docs: Get an actual User object from an identifier