UMEP fails to load on Linux Mint 22.3 / Python 3.12 — ModuleNotFoundError: No module named 'imp'

[nikosGeography]

System Information

• OS: Linux Mint 22.3 Zena (Ubuntu 24.04 Noble base)
• QGIS version: 3.44.9-Solothurn (installed from official qgis.org LTR repository)
• Python version: 3.12.3
• GDAL: 3.8.4
• GEOS: 3.12.1

UMEP fails to load after installation via the QGIS Plugin Manager, with the following error:

Couldn't load plugin 'UMEP' due to an error when calling its classFactory() method
ModuleNotFoundError: No module named 'future'

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/qgis/utils.py", line 478, in _startPlugin
    plugins[packageName] = package.classFactory(iface)
  File "/home/thedoctor/.local/share/QGIS/QGIS3/profiles/default/python/plugins/UMEP/__init__.py", line 42, in classFactory
    from .UMEP import UMEP
  File "/home/thedoctor/.local/share/QGIS/QGIS3/profiles/default/python/plugins/UMEP/UMEP.py", line 41, in <module>
    from .LCZ_Converter.LCZ_converter import LCZ_converter
  File "/home/thedoctor/.local/share/QGIS/QGIS3/profiles/default/python/plugins/UMEP/LCZ_Converter/LCZ_converter.py", line 24, in <module>
    from future import standard_library
ModuleNotFoundError: No module named 'future'

When I install python3-future via apt (sudo apt install python3-future), the module is found but a new error appears:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python3/dist-packages/future/standard_library/__init__.py", line 65, in <module>
    import imp
ModuleNotFoundError: No module named 'imp'

The imp module was removed in Python 3.12, and the version of python3-future available in the Ubuntu 24.04 apt repository is too old to support Python 3.12.

What I have tried

• Installed core dependencies via apt: sudo apt install python3-scipy python3-numpy python3-pandas python3-matplotlib python3-requests — these install and import successfully
• Installed python3-future via apt — installs but fails with No module named 'imp' as described above
• pip install is restricted by PEP 668 on Ubuntu 24.04 and cannot be used directly

Expected behaviour

UMEP should load successfully after installation.

Question

Is there a supported way to install UMEP on Python 3.12 / Ubuntu 24.04 based systems, where the imp module no longer exists? Has this been fixed in a development version, and if so, is there a recommended installation path for Linux Mint 22.3 users?

[biglimp]

@nilswallenberg or @j3r3m1 , could you assist? In the future, we should write some tips on how to do best practice linux installations...

[j3r3m1]

Hi @nikosGeography

It is not recommended to install python libraries via sudo apt because all the dependencies between libraries might not be solved. I recommend you to remove the libraries you have installed using this way, otherwise you will probably keep having troubles of dependencies in the future...

Instead I recommend you to use anaconda (with or without mamba): https://www.anaconda.com/docs/getting-started/anaconda/install/linux-install

Once installed, you should be able to create a virtual environment dedicated to the use of UMEP (or the use of QGIS). You can then install libraries within this environment not affecting your Python installation. You can use one Python environment by use and thus having different Python versions or libraries installed in each virtual environment.

In this discussion (#585 (comment)) you will find more informations about problems met by UMEP users with mamba.

Below is a minimum exemple of commands that should be used in your terminal to create a new environment, activate it and install needed Python libraries. After that, it might be necessary to install some more libraries (e.g. conda install conda-forge::future) when missing.

conda create --name your_conda_env
conda activate your_conda_env
conda config --add channels conda-forge
conda install gdal qgis jaydebeapi=1.2.3 numba netCDF4
qgis

Note that the last command is used to start QGIS from your conda environment, it might be the last QGIS version. Let us know if it works for you.

In the future, we should write some tips on how to do best practice linux installations...

Definitely. I think it would be nice to have a list of the needed libraries to install in order to simply have to run a conda command (or venv + pip) with this file.