Unable to import pytorch_lightning on google colab

Question

I have done the following:

!pip install pytorch_lightning -qqq
import pytorch_lightning

But get the following error:

ImportError                               Traceback (most recent call last)
<ipython-input-7-d883b15aac58> in <module>()
----> 1 import pytorch_lightning

----------------------------------9 frames------------------------------------------------
/usr/local/lib/python3.7/dist-packages/pytorch_lightning/utilities/apply_func.py in <module>()
     26 
     27 if _TORCHTEXT_AVAILABLE:
---> 28     from torchtext.data import Batch
     29 else:
     30     Batch = type(None)

ImportError: cannot import name 'Batch' from 'torchtext.data' (/usr/local/lib/python3.7/dist-packages/torchtext/data/__init__.py)

What could the issue be?

Answer 1

As said in Issue #6415 on Github, try installing from the GitHub.
It worked for me.

!pip install git+https://github.com/PyTorchLightning/pytorch-lightning
import pytorch_lightning as pl
print(pl.__version__)

Output:

1.3.0dev

It seems that the error is coming from Issue #6210 and they say it was fixed. I guess it wasn't uploaded to PyPi.

Answer 2

Example working env: https://colab.research.google.com/drive/1GSCd3Gz3EOQIln3v065VKWKbB3_F8xqK?usp=sharing

Can you try after restarting your env.

!pip install torchtext==0.8.0 torch==1.7.1 pytorch-lightning==1.2.2

import pytorch_lightning as pl
print(pl.__version__)
...

There appears to be a bug that has not hit pip yet with pytorch lightning not referencing the newest torchtext.

Answer 3

You can try this command, I encountered the same problem and was able to fix the problem.

!pip install --upgrade pytorch-lightning

Answer 4

Seems like the problem arises from the pytorch-lightning==1.1.x versions. Version above 1.2.x fixes the problem

But taking the latest version as in PythonSnek's answer resulted in some other bugs later on with the checkpoints saving. This could be because the latest version - 1.3.0dev is not still in development.

Installing the tar.gz of one of the stable versions fixes the problem

!pip install https://github.com/PyTorchLightning/pytorch-lightning/releases/download/1.2.6/pytorch-lightning-1.2.6.tar.gz 

Answer 5

Late, but if you are having similar difficulties with PyTorch Lightning Bolts you can solve it at the time of posting by making use of the same strategy:

!pip install git+https://github.com/PyTorchLightning/lightning-bolts

Answer 6

Doing the following installations solved my problem

pip install pytorch-lightning==1.4.4

pip install omegaconf -U

pip install hydra-core --upgrade

Source of Solution: https://github.com/PyTorchLightning/pytorch-lightning/issues/7110

Answer 7

may be you should upgrade your pytorch-lightning. My version is 1.4.0, when I upgrade it to 1.5.10. The error disappears.

Answer 8

PyTorch Lightning has been renamed to Lightning. For best support and fastest updates, install that version:

$ pip install lightning

and import it as:

import lightning as L

Since pytorch_lightning is a widely used framework, replacing its name can't be done overnight. For this reason, it is still kept and receives updates but the official framework is lightning.