Spyder sys.argv error: NameError: name 'basestring' is not defined

Question

UPDATE (2022-03-02): I discovered another nasty error. The Spyder IDE debugger doesn't work either. :-( The error is another namespace error (similar, but different from error below). I'm beginning to think I have a conflict from a package I installed last week.

TypeError: runfile() got an unexpected keyword argument 'current_namespace'

I have used Spyder IDE for several years without problems. Today I experienced a error with sys.argv usage in the IDE (only). (This is in a script I run several times a month over the past year.) I am trying to diagnose how/why this popped up. I have not change my Spyder installation (at least not intentionally). I recently installed the cartopy package and installed/removed basemap package. Spyder configuration:

E:\kcw78> list spyder
# packages in environment at C:\anaconda\Miniconda3:
# Name                    Version                   Build
pyls-spyder               0.3.2              pyhd3eb1b0_0
spyder                    4.2.0            py38haa95532_0
spyder-kernels            1.10.2           py38haa95532_0

Simple test code:

import sys
print(len(sys.argv))
print(sys.argv)

Behavior:
The script runs as expected when I execute it in a command window (w/ or w/out arguments).
Output below:

E:\kcw78> python test_sysargv.py
1
['test_sysargv.py']

E:\kcw78> python test_sysargv.py testval
2
['test_sysargv.py', 'testval']

I get different behavior when I run in the Spyder IDE.
It works if I don't enter any command line options (under Run/Configuration per file).
However, I get an error when I enter a value in Command line options. Error message in IPython console window:

runfile('E:/kcw78/test_sysargv.py', args='name.txt', wdir='E:/kcw78')
Traceback (most recent call last):

  File "C:\Windows\TEMP/ipykernel_5888/3729903912.py", line 1, in <module>
    runfile('E:/kcw78/test_sysargv.py', args='name.txt', wdir='E:/kcw78')

  File "C:\anaconda\Miniconda3\lib\site-packages\debugpy\_vendored\pydevd\_pydev_bundle\pydev_umd.py", line 147, in runfile
    if args is not None and not isinstance(args, basestring):

NameError: name 'basestring' is not defined

Any suggestions why I get different behavior for execution in Spyder vs command line? For example, configuration settings to check?