Set indent parameters for Python files

While working with python files written by others with varying indentation levels (some using 3 spaces and others using 4 spaces, and some mixing tabs and spaces), it gets tiresome to determine the right settings and change them manually. While looking for a good script to this automatically, I came across two scripts. The first one on the vim scripts page called DetectIndent, but it didn't work well for some of the python files I tried (some being set to shiftwidth of 1). The other one I found is a python script called vindect. The comment in the file has a suggested setup, but here is what worked better for me:

• Download and extract the python file.
• Copy it as vindent.py (without the version number in the filename) to your .vim or vimfiles directory.
• Create a after/ftplugin/python.vim file with the below contents (change vimfiles to .vim accordingly):

if !exists('s:configured_vindect')
   if has("python")
      py import sys,os; sys.path.append(os.path.expanduser("~/vimfiles/"))
      try
         py import vindect
         let s:configured_vindect = 1
      catch
         let s:configured_vindect = 0
      endtry
      "if you want different defaults: py vindect.setDefaults(...)
   else
      let s:configured_vindect = 0
   endif
endif

if s:configured_vindect
   py vindect.detect() 
endif