docs: def make_tls_property(default=None):
      """Creates a class-wide instance property with a thread-specific value."""
      class TLSProperty(object):
          def __init__(self):
              from threading import local
              self.local = local()
  
          def __get__(self, instance, cls):
              if not instance:
                  return self
              return self.value
  
          def __set__(self, instance, value):
              self.value = value
  
          def _get_value(self):
              return getattr(self.local, 'value', default)
          def _set_value(self, value):
              self.local.value = value
          value = property(_get_value, _set_value)
  
      return TLSProperty()