ModuleNotFoundError+No+module+named+psycopg2

Not specified by the original author.

How to fix ModuleNotFoundError: No module named 'psycopg2'

SQLAlchemy does not ship a Postgres driver; a bare postgresql:// URL defaults to psycopg2. Install it: pip install psycopg2-binary (no compiler needed), or switch the URL to the v3 driver you do have: postgresql+psycopg://... with pip install "psycopg[binary]". The driver name in the URL must match the installed package.

The exact error

ModuleNotFoundError: No module named 'psycopg2'

Fix it

1. Check which driver you have: python -m pip show psycopg2-binary psycopg. Expected: you see which (if any) is installed

2. Easiest: python -m pip install psycopg2-binary and keep postgresql://. Expected: create_engine connects

3. Or go v3: python -m pip install "psycopg[binary]" and change the URL to postgresql+psycopg://host/db. Expected: connects via psycopg3

When this applies

create_engine('postgresql://...') raises No module named 'psycopg2'

When this does NOT apply

NoSuchModuleError: Can't load plugin for a different dialect (that is a URL/dialect mismatch)

Versions

SQLAlchemy with postgresql:// URLs

Why it happens

DBAPI drivers are separate packages by design; SQLAlchemy only knows the dialect name.

Edge cases

psycopg2 from source needs pg_config/libpq headers to build; psycopg2-binary avoids that. Keep the password in env vars, not code.

Asked about: ModuleNotFoundError: No module named 'psycopg2' (gh:zzstoatzz/plyr.fm#1584). The verified fix: SQLAlchemy does not ship a Postgres driver; a bare postgresql:// URL defaults to psycopg2. Install it: pip install psycopg2-binary (no compiler needed), or switch the URL to the v3 driver you do have: postgresql+psycopg://... with pip install "psycopg[binary]". The driver name in the URL must match the installed package. Full thread: https://github.com/zzstoatzz/plyr.fm/issues/1584

Not specified by the original author.

ModuleNotFoundError: No module named 'keycloak'

TL;DR: the distribution is called python-keycloak, not keycloak. Run pip install python-keycloak and the import works.

ModuleNotFoundError: No module named 'keycloak'

The fix

pip install python-keycloak

Verify:

python -c "from keycloak import KeycloakOpenID; print('ok')"

Expected output: ok.

Agent? Search Vectle for more: curl -s 'https://vectle.com/api/v1/search?q=python-keycloak+No+module+named+keycloak'

When this applies

• First-time Keycloak integration in Python.
• Fresh virtualenvs, containers, or CI runners.
• You ran pip install keycloak and the import still failed.

When it does NOT apply

• Connection errors to the Keycloak server, which happen after the import works.
• keycloak.exceptions errors, which are runtime API errors, not import errors.

Why this happens

The keycloak name on PyPI does not belong to this project, so the distribution took the python- prefixed name while the module kept the clean one. pip installs exactly what you name; the ModuleNotFoundError persists until you use the real distribution name.

Compatibility

python-keycloak 3.x/4.x/5.x. Works against Keycloak servers 18+; check the compatibility matrix in the docs for older servers.

The module is keycloak but the distribution is python-keycloak, so pip install keycloak does not provide the expected API. The python-keycloak project page documents pip install python-keycloak as the install command. This is the same naming trap as python-jose and python-gnupg, and it bites everyone integrating Keycloak auth into Python for the first time.

Not specified by the original author.

TL;DR

Kernels tried: condapytorchp36 , condapython3 , condaamazoneimxnetp27. ! pip install farm-haystack -q # Install the latest master of Haystack !pip install grpcio-tools==1.34.1 -q !pip install git+https://github.com/deepset-ai/haystack.git -q !wget --no-check-certificate https://dl.xpdfreader.com/xpdf-tools-linux-4.03.tar.gz !tar -xvf xpdf-tools-linux-4.03.tar.gz && sudo cp xpdf-tools-linux-4.03/bi

Steps

1. I would recommend to downgrade your milvus version to a version before the 2.0 release just a week ago. Here is a discussion on that topic: https://github.com/deepset-ai/haystack/issues/2081

When to use

You are seeing this: I would recommend to downgrade your milvus version to a version before the 2.0 release just a week ago. Use this skill when you run into "ModuleNotFoundError: No module named 'milvus'".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

Versions mentioned in the source: grpcio-tools 1.34.1. If you are on something much newer or older, the details may have shifted.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Sources

• https://github.com/deepset-ai/haystack/issues/2081
• https://github.com/deepset-ai/haystack.git
• https://dl.xpdfreader.com/xpdf-tools-linux-4.03.tar.gz

Source: Goal: to run this Auto Labelling Notebook on AWS SageMaker Jupyter Labs. Kernels tried: condapytorchp36 , condapython3 , condaamazoneimxnetp27 . ! pip install farm-haystack -q # Install the latest master of Haystack !pip install grpcio-tools==1.34.1 -q !pip install git+https://github.com/deepset-ai/haystack.git -q !wget --no-check-certificate https://dl.xpdfreader.com/xpdf-tools-linux-4.03.tar.gz !tar -xvf xpdf-tools-linux-4.03.tar.gz && sudo cp xpdf-tools-linux-4.03/bi

Verified resolution: I would recommend to downgrade your milvus version to a version before the 2.0 release just a week ago. Here is a discussion on that topic: https://github.com/deepset-ai/haystack/issues/2081

Source URL: https://stackoverflow.com/questions/70954157/modulenotfounderror-no-module-named-milvus