Kernel is DOA for Linux-based Jupyter notebook (and Jupyter lab) - python-3.x

Question

So, after some trial-and-error, I managed to install Jupyter and its key GUIs (notebook and lab) using pip3. The jupyter notebook and the jupyterlab applications load fine. Whenever I try to create or access a notebook, however, the kernel is DOA. I tried restarting it without any luck. This is regardless of what language this kernel corresponds to (so it's not a language-specific problem). I encounter a similar question where the solution was ownership of the files in a certain folder, so I made sure that I maintain ownership of these files with my usual user (not root). Still, the problem persists. If you have any ideas as to how to resolve it, I'd be grateful. Cheers
Here is the error message I get, BTW:
Traceback (most recent call last):
File "/home/[my username]/.local/lib/python3.6/site-packages/tornado/web.py", line 1704, in _execute
result = await result
File "/home/[my username]/.local/lib/python3.6/site-packages/tornado/gen.py", line 769, in run
yielded = self.gen.throw(*exc_info) # type: ignore
File "/home/[my username]/.local/lib/python3.6/site-packages/notebook/services/sessions/handlers.py", line 72, in post
type=mtype))
File "/home/[my username]/.local/lib/python3.6/site-packages/tornado/gen.py", line 762, in run
value = future.result()
File "/home/[my username]/.local/lib/python3.6/site-packages/tornado/gen.py", line 769, in run
yielded = self.gen.throw(*exc_info) # type: ignore
File "/home/[my username]/.local/lib/python3.6/site-packages/notebook/services/sessions/sessionmanager.py", line 88, in create_session
kernel_id = yield self.start_kernel_for_session(session_id, path, name, type, kernel_name)
File "/home/[my username]/.local/lib/python3.6/site-packages/tornado/gen.py", line 762, in run
value = future.result()
File "/home/[my username]/.local/lib/python3.6/site-packages/tornado/gen.py", line 769, in run
yielded = self.gen.throw(*exc_info) # type: ignore
File "/home/[my username]/.local/lib/python3.6/site-packages/notebook/services/sessions/sessionmanager.py", line 101, in start_kernel_for_session
self.kernel_manager.start_kernel(path=kernel_path, kernel_name=kernel_name)
File "/home/[my username]/.local/lib/python3.6/site-packages/tornado/gen.py", line 762, in run
value = future.result()
File "/home/[my username]/.local/lib/python3.6/site-packages/notebook/services/kernels/kernelmanager.py", line 176, in start_kernel
kernel_id = await maybe_future(self.pinned_superclass.start_kernel(self, **kwargs))
File "/home/[my username]/.local/lib/python3.6/site-packages/jupyter_client/multikernelmanager.py", line 184, in start_kernel
km, kernel_name, kernel_id = self.pre_start_kernel(kernel_name, kwargs)
File "/home/[my username]/.local/lib/python3.6/site-packages/jupyter_client/multikernelmanager.py", line 172, in pre_start_kernel
**constructor_kwargs
File "/home/[my username]/.local/lib/python3.6/site-packages/jupyter_client/multikernelmanager.py", line 83, in create_kernel_manager
km = kernel_manager_ctor(*args, **kwargs)
File "/home/[my username]/.local/lib/python3.6/site-packages/traitlets/config/configurable.py", line 73, in __init__
super(Configurable, self).__init__(**kwargs)
File "/home/[my username]/.local/lib/python3.6/site-packages/traitlets/traitlets.py", line 1000, in __init__
super_kwargs[key] = value
File "/usr/lib/python3.6/contextlib.py", line 88, in __exit__
next(self.gen)
File "/home/[my username]/.local/lib/python3.6/site-packages/traitlets/traitlets.py", line 1131, in hold_trait_notifications
self.notify_change(change)
File "/home/[my username]/.local/lib/python3.6/site-packages/traitlets/traitlets.py", line 1176, in notify_change
c(change)
File "/home/[my username]/.local/lib/python3.6/site-packages/traitlets/traitlets.py", line 819, in compatible_observer
return func(self, change)
TypeError: _kernel_spec_manager_changed() takes 1 positional argument but 2 were given