python 2.7 functools_lru_cache does not import although installed

Question

When I try to import matplotlib I get an error

Traceback (most recent call last):
  File \"\", line 1, in 
  File \"/usr/local/lib         


        

Answer 1

This worked for me. Ubuntu 18.04.

sudo pip2 uninstall backports.functools-lru-cache
sudo apt install python-backports.functools-lru-cache

Answer 2

I had the same problem and my solution was;

• Download whl file from https://pypi.python.org/pypi/backports.functools_lru_cache/1.3

• pip install

Answer 3

I solved my problem by removing the excessive matplotlib packages. I found out that when importing matplotlib it was attempting to import backports.functools_lru_cache and there it was throwing the Importerror.

I realized that I had different matplotlib packages in many locations:

/usr/lib/python2.7/dist-packages/matplotlib/
/usr/lib/python2.7/site-packages/matplotlib/

I removed the site-packages one. I left the dist-packages one intact.

Then I ran the following commands in python:

matplotlib.get_configdir()
matplotlib.get_cachedir()

and I removed the matplotlib packages in the output paths of these commands.

Then I removed the matplotlib in my virtualenvironment:

mv /home/username/virtualenvironment/lib/python2.7/matplotlib* /tmp

Finally I removed the one in the .local folder:

mv /home/username/.local/lib/python2.7/matplotlib* /tmp

Now importing matplotlib works fine. So when I run in python:

matplotlib.__file__

it returns

'/usr/lib/python2.7/dist-packages/matplotlib/__init__.pyc'

Now it does not throw error anymore when import backports.functools_lru_cache

Answer 4

Following from Aditya Jain's answer,

[python -m] pip uninstall backports.functools_lru_cache
[python -m] pip install backports.functools_lru_cache==1.2.1

which will avoid installing arrow merely to downgrade functools_lru_cache.

Answer 5

You have to check what is the import path of backports package:

import backports
print('Backports Path: {0}'.format(backports.__path__))

1. The import path is the main python path ( the case of Matimath's question)

pip uninstall backports.functools_lru_cache   (this will uninstall it from /usr/local/)
pip install backports.functools_lru_cache

2. The import path is the local usr dir (~/.local/, or %APPDATA%\Python for windows)

pip uninstall backports.functools_lru_cache 
pip install --user backports.functools_lru_cache

Use pip2 command for python2.

The reason for this inconsistency is that the import path of backports package might have been changed during another module/package installation (eg. from backports.configparser module) - see here for more details: https://bugs.python.org/issue31741

Answer 6

this worked for me

from backports.functools_lru_cache import lru_cache