Linux install fails on a pi zero and on Linux Mint

I've had much better luck trying to install inkcut on a pi zero and I'd like to continue that route if possible.

After trying

pip3 install inkcut

I get:

  ERROR: Could not find a version that satisfies the requirement pycups; sys_platform == "linux" (from inkcut) (from versions: none)
ERROR: No matching distribution found for pycups; sys_platform == "linux" (from inkcut)

I checked the python version, and although I thought I had upgraded to Python 3, I got:

Python 2.7.16

So I'm not sure how to proceed from here.

pi@inkcut-server:~ $ sudo apt-get install python3-pycups Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package python3-pycups pi@inkcut-server:~ $ sudo apt install python3-pycups Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package python3-pycups
pi@inkcut-server:~ $ sudo apt-get install python3-pycups
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package python3-pycups

pi@inkcut-server:~ $ sudo apt install python3-pycups
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package python3-pycups

Sorry. Is that what you meant? I'm not finding those packages

Edit: Also. pypi.org/project/pycups/

returns:

pi@inkcut-server:~ $ pip install pycups 
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple Collecting pycups 
ERROR: Could not find a version that satisfies the requirement pycups (from versions: none) 
ERROR: No matching distribution found for pycups

NP. I used:

pi@inkcut-server:~ $ sudo apt-get install python3-cups

and it installed

The following NEW packages will be installed: python3-cups 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. 

Need to get 52.9 kB of archives. 
After this operation, 348 kB of additional disk space will be used. 
Get:1 http://mirror.sjc02.svwh.net/raspbian/raspbian buster/main armhf python3-cups armhf 1.9.73-2+b1 [52.9 kB] 
Fetched 52.9 kB in 1s (38.3 kB/s) 
Selecting previously unselected package python3-cups. 
(Reading database ... 146201 files and directories currently installed.) 
Preparing to unpack .../python3-cups_1.9.73-2+b1_armhf.deb ...
 Unpacking python3-cups (1.9.73-2+b1) ...
 Setting up python3-cups (1.9.73-2+b1) ...

But trying

pip3 install inkcut

again gives an error.

pi@inkcut-server:~ $ pip3 install inkcut
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: inkcut in /usr/local/lib/python3.6/site-packages/inkcut-2.1.1.dev0-py3.6.egg (2.1.1.dev0)
  Ignoring faulthandler: markers 'python_version < "3.0"' don't match your environment
  Ignoring pycups: markers 'sys_platform == "linux2"' don't match your environment
  Ignoring pywin32: markers 'sys_platform == "win32"' don't match your environment
Collecting enaml>=0.10 (from inkcut)
  Using cached https://files.pythonhosted.org/packages/3e/48/d9aa26bb2850dd9a7c48f173faad03273d92f65c6096ca9555308ba194de/enaml-0.10.3.tar.gz
Collecting twisted (from inkcut)
  Using cached https://www.piwheels.org/simple/twisted/Twisted-16.3.2-py3-none-any.whl
Collecting enamlx>=0.4.1 (from inkcut)
  Using cached https://files.pythonhosted.org/packages/cb/f7/48efe7f1b91d91e879e9b762d2cdcbe166edaf03a8989f46a43c938d868a/enamlx-0.4.1-py2.py3-none-any.whl
Collecting pyqtgraph (from inkcut)
  Using cached https://www.piwheels.org/simple/pyqtgraph/pyqtgraph-0.10.0-py3-none-any.whl
Collecting qtconsole (from inkcut)
  Using cached https://files.pythonhosted.org/packages/79/0b/efb5a694b6922bb85c35e4f1db6197daae23c764dd384023fc9517d79e26/qtconsole-4.5.1-py2.py3-none-any.whl
Collecting pyserial>=3.4 (from inkcut)
  Using cached https://files.pythonhosted.org/packages/0d/e4/2a744dd9e3be04a0c0907414e2a01a7c88bb3915cbe3c8cc06e209f59c30/pyserial-3.4-py2.py3-none-any.whl
Collecting jsonpickle (from inkcut)
  Using cached https://files.pythonhosted.org/packages/07/07/c157520a3ebd166c8c24c6ae0ecae7c3968eb4653ff0e5af369bb82f004d/jsonpickle-1.2-py2.py3-none-any.whl
Collecting lxml (from inkcut)
  Using cached https://files.pythonhosted.org/packages/da/b5/d3e0d22649c63e92cb0902847da9ae155c1e801178ab5d272308f35f726e/lxml-4.3.4.tar.gz
Collecting qt-reactor (from inkcut)
  Using cached https://files.pythonhosted.org/packages/83/77/506a082b80c43fc50509f13c1aed9b63716295f3f0f983035b8bb49f6e23/qt_reactor-0.6-py2.py3-none-any.whl
Collecting pycups; sys_platform == "linux" (from inkcut)
  ERROR: Could not find a version that satisfies the requirement pycups; sys_platform == "linux" (from inkcut) (from versions: none)
ERROR: No matching distribution found for pycups; sys_platform == "linux" (from inkcut)

I'm using the latest Debian version of Raspbian which is Buster. Could that be the issue?