I got NameError for calling test_gobject, but the funny thing is I never called this function name. I called test_gobjectpy()
Can you explain it to me why Python decide to call the wrong function name (see error output)

Maybe it has some problems because I have a string with the same name as function?!

file name test_dyn_fun.py

second_path = ['test_gobject.py', 'st1.py', 'test_show_desktop.py', 'download_img.py', 'test_dump.py']
print("second_path", second_path)
print()
for i in second_path:
    #func = create_dyn_func(i)
    tmp = i.replace(".", "")  #rm dot for function name
    print("tmp =", tmp)
    exec(f"def {tmp}(): print({i})")
print()
print(dir(test_gobjectpy))
print()
print(locals())
test_gobjectpy()

Error output:

Traceback (most recent call last):
  File "/home/manta/Coding/test_dyn_fun.py", line 13, in <module>
    test_gobjectpy()
  File "<string>", line 1, in test_gobjectpy
NameError: name 'test_gobject' is not defined

CodePudding user response：

In your loop you create functions, the first one created is effectively created like this:

i = 'test_gobject.py' 
tmp = 'test_gobjectpy'
exec(f"def {tmp}(): print({i})")

So, it's as if you ran:

exec("def test_gobjectpy(): print(test_gobject.py)")

For Python to print test_gobject.py, it tries to access an object called test_gobject and its attribute .py.

That's what is causing the error. The fact that test_gobject.py looks like a filename to you doesn't matter, it's just names of variables to Python, the way you wrote it.

What would you expect to happen if you called this function?

def test_gobjectpy():
    print(test_gobject.py)

More in general, as a beginning programmer, it's generally best to stay away from stuff like exec() and eval(). It's very common for new Python programmers to think they need this, or that it somehow solves a problem they have, but it's generally the worst solution to the problem and rarely actually a good solution at all. (not never, just rarely)