Useful VIM Settings for working with Python:

Setting Abbr. Explanation
tabstop=4 ts A four-space tab indent width is the prefered coding style for Python (and everything else!), although of course some disagree. This page generally assumes you want 4-space indents.
shiftwidth=4 sw This allows you to use the < and > keys from VIM's visual (marking) mode to block indent/unindent regions
smarttab sta Use the "shiftwidth" setting for inserting <TAB>s instead of the "tabstop" setting, when at the beginning of a line. This may be redundant for most people, but some poeple like to keep their tabstop=8 for compatability when loading files, but setting shiftwidth=4 for nicer coding style.
expandtab et Insert spaces instead of <TAB> character when the <TAB> key is pressed. This is also the prefered method of Python coding, since Python is especially sensitive to problems with indenting which can occur when people load files in different editors with different tab settings, and also cutting and pasting between applications (ie email/news for example) can result in problems. It is safer and more portable to use spaces for indenting.
softtabstop=4 sts People like using real tab character instead of spaces because it makes it easier when pressing BACKSPACE or DELETE, since if the indent is using spaces it will take 4 keystrokes to delete the indent. Using this setting, however, makes VIM see multiple space characters as tabstops, and so <BS> does the right thing and will delete four spaces (assuming 4 is your setting).
autoindent ai Very painful to live without this (especially with Python)! It means that when you press RETURN and a new line is created, the indent of the new line will match that of the previous line.
Remember. You can do :help command to get more info on these settings from inside VIM.


More complicated settings:


The following line sets the smartindent mode for *.py files. It means that after typing lines which start with any of the keywords in the list (ie. def, class, if, etc) the next line will automatically indent itself to the next level of indentation:

autocmd BufRead *.py set smartindent cinwords=if,elif,else,for,while,try,except,finally,def,class

Another approach is to create a key mapping which detects when you type a colon (:) followed by a RETURN (<CR>), and adds a <TAB> keypress to the end.

im :<CR> :<CR><TAB>

Trim Trailing Whitespace

Many people like to remove any extra whitespace from the ends of lines. Here is one way to do it when saving your file.

autocmd BufWritePre *.py normal m`:%s/\s\+$//e ``

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