If that's the only code you have then, yes, you set (for example) q1 to a value but never use it after that.

If you've failed to show us code outside of those functions that uses q1, it still is not being used.

That's because, if you assign to a variable (like q1 = 42) within a function and that variable is not explicitly marked global, it will be a new local variable within the function, not one already existing in a containing namespace.

That is because VS code detecte that code as dead code which is not going to be used in the program. It will get clearer from the example below:

 b = "hello"
 def abc():
     a = input('enter first number')
     return a
 abc()

In the example above b is never used, so it is detected as dead code by VS code. VS code refers to these statements as not accessed. But the code assigning the variable will still get executed.

In your case, dealer is not used in the program so VS code finds it as dead code.

num is assigned as part of the list comprehension, but is then never used. You'd get the exact same output if you replaced num with an underscore (_), so the warning seems to be correct:

my_list: list[str] = ["MFI BL {num}" for _ in range(1, 15)]
# Here ----------------------------------^

It looks like you meant to use an f-string, in which case the {num} placeholder would be evaluated, and the warning would be resolved:

my_list: list[str] = [f"MFI BL {num}" for num in range(1, 15)]
# Here ---------------^

The error you show is one given by your editor, not by Python. Pylance is an extension for Visual Studio Code (VSCode) to help the editor understand Python code. It simply means that Pylance is not using the same Python binary as your project.

Open the command palette and type "Python: select interpreter", then find your Python interpreter that has pyodbc installed. See the documentation on using Python environments.

Note that even with as single Python installation, you can have multiple virtual environments. You may have installed PyODBC in a virtual environment, or in the system Python packages, but if Pylance is looking at the wrong environment it won't find PyODBC.