I have runned: `pip install pytorch-lightning`, but get error: No module named `pytorch_lightning`

[muyuuuu]

Discussed in #11498

^{Originally posted by muyuuuu January 16, 2022}

python: 3.8.8
pytorch: 1.7.0
pytorch-lightning: 1.5.8
windows 10 and anaconda 4.11.0

[semaphore-egg]

This issue probably is not related to lightning.

Check if lightning is successfully installed in correct environments and activate the environment before running the code.
Following commands might help:
which pip
pip list
conda env list
conda activate env_name

[akihironitta]

@muyuuuu Would you mind trying @semaphore-egg's suggestion? Or you could also try:

python -m pip install pytorch-lightning

[muyuuuu]

1. /c/programData/Miniconda3/Scripts/pip
2. pip list shows pytorch-lightning: 1.5.8
3. I didn't create virtual environment

[estathop]

@muyuuuu Would you mind trying @semaphore-egg's suggestion? Or you could also try:

python -m pip install pytorch-lightning

This solved the case for me in MACOSX and MacBook Air early 2015