Cheers Jack.

Yes, I installed python 3 with:

$ sudo apt-get install python3-setuptools python3-pyqt5 python3-pip
[sudo] password for beans9:
Reading package lists... Done
Building dependency tree       
Reading state information... Done
python3-setuptools is already the newest version (20.7.0-1).
python3-pyqt5 is already the newest version (5.5.1+dfsg-3ubuntu4).
python3-pip is already the newest version (8.1.1-2ubuntu0.4).
0 to upgrade, 0 to newly install, 0 to remove and 5 not to upgrade.

When I check the version of python with:

python3.6 -V

It reports:

Python 3.6.7

But it fails when installing electrum itself, ie:

sudo python3 -m pip install https://download.electrum.org/3.3.2/Electrum-3.3.2.tar.gz#egg=electrum[fast]

produces:

The directory '/home/my idrectory/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/home/my idrectory/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been disabled.

    Error: Electrum requires Python version >= 3.6.1...
   
    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-3246txsb/electrum/
You are using pip version 8.1.1, however version 18.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.

---

When I try to upgrade pip with

sudo pip install --upgrade pip

I get this:

/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/__init__.py:83: RequestsDependencyWarning: Old version of cryptography ([1, 2, 3]) may cause slowdown.
  warnings.warn(warning, RequestsDependencyWarning)

Requirement already up-to-date: pip in /usr/local/lib/python2.7/dist-packages (18.1)

Note the references to python 2.7.

I don't know how to get past this.

---

Looking for 'python' folders in /usr/local/lib I have 'python3.6', but no files in there, which seems odd.

I have been happily using electrum in my linux mint OS for some time but it has failed to receive a payment and gets stuck on 'Synchronising'. I have tried to upgrade electrum to version 3.3.2, but I get the following error messages:

The directory '/home/my idrectory/.cache/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.
The directory '/home/my idrectory/.cache/pip' or its parent directory is not owned by the current user and caching wheels has been disabled.

    Error: Electrum requires Python version >= 3.6.1...
   
    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-3246txsb/electrum/
You are using pip version 8.1.1, however version 18.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.

I have tried the following:

- upgrading via pip install using 'pip install --upgrade pip' command.
- 'pip install --upgrade setuptools'
- 'pip install --upgrade setuptools --user python'

but I get the same error message.


I have tried:

sudo apt-get install python3.5-dev libmysqlclient-dev
sudo apt-get install python3-numpy

but get the same error message.

Would anyone have any ideas?

Thank you!