I get this error when I try to execute the example https://github.com/pytorch/ignite/blob/master/examples/mnist/mnist_with_tensorboardx.py 1
Traceback (most recent call last):
  File "/content/mnist_with_tensorboardx.py", line 130, in <module>
    args.log_interval, args.log_dir)
  File "/content/mnist_with_tensorboardx.py", line 76, in run
    @trainer.on(Events.ITERATION_COMPLETED(every=log_interval))
TypeError: 'Events' object is not callable

I’m working on google colab so I had to install some packages and I also used  TensorBoard notebook extension:
!pip install --pre pytorch-ignite
!pip install 'grpcio==1.24.3'
!pip install -q tf-nightly-2.0-preview
%load_ext tensorboard 
!python /content/mnist_with_tensorboardx.py --log_dir=/tmp/tensorboard_logs
%tensorboard --logdir {/tmp/tensorboard_logs}

According to this issue https://github.com/pytorch/ignite/issues/687 1, the problem is solved when the latest nightly version is used however for me it’s not the case.