Install failure: LGPL License Classifier

Label Studio Support
1

Hello!

I’m running Windows 11; I’m having essentially the same problem in cmd and in WSL2 running Ubuntu Noble Numbat 24.04.03.

I’m trying to install label-studio; `pip install –upgrade label-studio` eventually fails with

× Failed to build installable wheels for some pyproject.toml based projects
╰─> psycopg2-binary, pyarrow

I have installed both pyarrow and postgreSQL.

These ‘install on Ubuntu’ instructions use Python 3.9 (which is EOL) and end up with the same result

python3 -m venv env
source env/bin/activate
sudo apt install python3.9-dev
python -m pip install label-studio

I can’t upload attachments, but lines 534-543 of the output are

  /tmp/pip-build-env-53smsnci/overlay/lib/python3.14/site-packages/setuptools/dist.py:759: SetuptoolsDeprecationWarning: License classifiers are deprecated.
  !!

          ********************************************************************************
          Please consider removing the following classifiers in favor of a SPDX license expression:

          License :: OSI Approved :: GNU Library or Lesser General Public License (LGPL)

          See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
          ********************************************************************************

Is that part of the label-studio script, or is that something I can fix? How do I move past this?

2

I installed conda and tried the conda instructions, which gave me output ending in…

  running build_ext
  creating /tmp/pip-install-b5ubz552/pyarrow_c64bb86230a946b0b7ab2cd551d4f65e/build/temp.linux-x86_64-cpython-314
  -- Running cmake for PyArrow
  cmake -DCMAKE_INSTALL_PREFIX=/tmp/pip-install-b5ubz552/pyarrow_c64bb86230a946b0b7ab2cd551d4f65e/build/lib.linux-x86_64-cpython-314/pyarrow -DPYTHON_EXECUTABLE=/usr/local/bin/python3 -DPython3_EXECUTABLE=/usr/local/bin/python3 -DPYARROW_CXXFLAGS= -DPYARROW_BUNDLE_ARROW_CPP=off -DPYARROW_BUNDLE_CYTHON_CPP=off -DPYARROW_GENERATE_COVERAGE=off -DCMAKE_BUILD_TYPE=release /tmp/pip-install-b5ubz552/pyarrow_c64bb86230a946b0b7ab2cd551d4f65e
  error: command 'cmake' failed: No such file or directory
  [end of output]

note: This error originates from a subprocess, and is likely not a problem with pip.
ERROR: Failed building wheel for pyarrow
Failed to build pyarrow
error: failed-wheel-build-for-install

× Failed to build installable wheels for some pyproject.toml based projects
╰─> pyarrow

3

I’m seeing the same problem on my MacBook… any chance you found a solution?
I’ve tried

  • adding license = “MIT” to the [project] section in my pyproject.toml file.

  • installing the PyPI ‘psycopg2-binary’ package

I’m not using setup.py, I’m using pyproject.toml, so I’m not sure what do with the suggestion:

      pg_config is required to build psycopg2 from source.  Please add the directory containing pg_config to the $PATH or specify the full executable path with the option:
      
          python setup.py build_ext --pg-config /path/to/pg_config build ...
      
      or with the pg_config option in 'setup.cfg'.

Edit: I got around the issue by following the instructions to install via homebrew (Label Studio Documentation — Install and Upgrade Label Studio). From there I was able to update label-studio with pip commands. Weird.