code: def get_task_var(self, key, default=None):
          
          if self._task_vars:
              if self.delegate_to_hostname is None:
                  if key in self._task_vars:
                      return self._task_vars[key]
              else:
                  delegated_vars = self._task_vars['ansible_delegated_vars']
                  if self.delegate_to_hostname in delegated_vars:
                      task_vars = delegated_vars[self.delegate_to_hostname]
                      if key in task_vars:
                          return task_vars[key]
  
          return default
docs: Fetch the value of a task variable related to connection configuration,
          or, if delegate_to is active, fetch the same variable via HostVars for
          the delegated-to machine.
  
          When running with delegate_to, Ansible tasks have variables associated
          with the original machine, not the delegated-to machine, therefore it
          does not make sense to extract connection-related configuration for the
          delegated-to machine from them.