Today I installed python 3.7 from apt-get to try out the new dataclasses module. I installed it seperately because python3.6 wasn't upgradeable to 3.7.
When I type: python3.7 --version, it gives me: >>> Python 3.7.0a2 as my current version.
The problem is that I can't seem to import dataclasses.
my import statement is: from dataclasses import dataclass as instructed here
This is the error message it's giving me:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ModuleNotFoundError: No module named 'dataclasses'
Error in sys.excepthook:
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63, in apport_excepthook
from apport.fileutils import likely_packaged, get_recent_crashes
File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in <module>
from apport.report import Report
File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in <module>
import apport.fileutils
File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23, in <module>
from apport.packaging_impl import impl as packaging
File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line 24, in <module>
import apt
File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in <module>
import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'
Original exception was:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ModuleNotFoundError: No module named 'dataclasses'
I even tried installing the dataclasses module with pip3: pip3 install dataclasses. Not sure if that's necessary though.
Any suggestion on what might be the problem?
[EDIT] Just tried it with a python3.6 console and it worked fine .. weird.
1 Answer
As suggested by @wim python3.7 -m venv venv_dir
This command will:
- Use python3.7 to run the command
- The
-mflag tells the interpreter to run the next argument as a script venvis a module, and because of the-mflag it will be run as a script- Finally, the
venv_diris given to thevenvmodule as an argument which this module will use to create a virtual environment directory at
Once this command is run now you'll have a nice sandbox for messing around/testing the dataclasses module.
- To activate this virtual environment be sure to run
source venv_dir/bin/activatebefore you begin. This command will run the script atvenv_dir/bin/activateto set up the necessary environment variables and other things for you - To deactivate, simply run
deactivateafter activating