ivanov/vim-ipython — pull request #72 by marcel-wolf (2013-08-28 20:40:13+00:00)
Title: invoke IPython's run magic as %run instead of run

If the source file defines or imports a symbol named 'run', that symbol
takes precedence over IPython's run, leading to a syntax error being
thrown when invoking run_this_file()

Using %run removes the ambiguity.