vim and python scripts debugging

Use pdb:

import pdb
def main():
  list = [1,2,3]
  pdb.set_trace()
  list = [2,3,4]

if __name__ == '__main__':
    main()

Now run using :!python % and you'll hit your breakpoint and be able to debug interactively like in gdb.

As of Python 3.7, you can use breakpoint() builtin without importing anything.

Built-in breakpoint() calls sys.breakpointhook(). By default, the latter imports pdb and then calls pdb.set_trace()

Inheriting code from Pierre-Antoine's answer, the code would look like this:

def main():
  list = [1,2,3]
  breakpoint()
  list = [2,3,4]

if __name__ == '__main__':
    main()

_{Source: https://docs.python.org/3/whatsnew/3.7.html#pep-553-built-in-breakpoint}

As 2020 the Debugger Adapter Protocol is taken care by vimspector. Supporting Cpp, Python, Java, Js, Go ... See my other answer

The vimpdb plugin integrates the Python debugger pdb into the VIM editor.

I do recommend it.

Hope it helps.

See the "Debugging" section in this blog post. It shows how to setup F7 to set breakpoints and Shift+F7 to remove breakpoints. It also uses pdb, as mentioned before. With a little modification, you can replace the use of pdb with ipdb (pdb using ipython), which is a lot nicer to use.

It sounds like you want to use VIM as a Python IDE.

A quick Google search found this and this example, with many more.

EDIT: Well, Ok, it seems likely you've searched more than I have.

I hope someone else has some ideas.

From what I know, there is one more option: You could use Eclipse + PyDev for project managing and Vim as an editor for Eclipse. That way You could use the best of both worlds.

Also, I haven't tried it, but You could try this script.